Titanium-containing film forming compositions for vapor deposition of titanium-containing films

ABSTRACT

Titanium-containing film forming compositions comprising titanium halide-containing precursors are disclosed. Also disclosed are methods of synthesizing and using the disclosed precursors to deposit Titanium-containing films on one or more substrates via vapor deposition processes.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a divisional of U.S. application Ser. No.15/968,099, filed May 1, 2018, which is a continuation-in-part of U.S.application Ser. No. 15/827,783 filed Nov. 30, 2017, herein incorporatedby reference in its entirety for all purposes.

TECHNICAL FIELD

Disclosed are Ti-containing film forming compositions comprisingtitanium halide-containing precursors. Also disclosed are methods ofsynthesizing and using the disclosed precursors to deposittitanium-containing films on one or more substrates via vapor depositionprocesses.

BACKGROUND

With the scaling down of semiconductor devices, new materials with highdielectric constant are required. Chemical Vapor Deposition (CVD) andAtomic Layer Deposition (ALD) have become the main deposition techniquesfor such thin films. CVD and ALD may provide different films (metal,oxide, nitride, etc.) having a finely defined thickness and high stepcoverage. In CVD and ALD, the precursor molecule plays a critical roleto obtain high quality films with high conformality and low impurities.

Among high-k dielectrics, titanium based materials, such as TiO₂, arevery promising, whether used as pure or mixed oxides or in laminates.TiN may be used for electrode and/or Cu diffusion barrier applications.Titanium oxides may also be used for their etch resistance properties inlithography applications, such as for hard masks or spacer-definedmultiple patterning applications. Titanium silicides may serves as acontact between conductive plugs and the underlying doped silicon layer.

Synthesis and characterization of a variety of titanium halide Lewisadducts is known. See, e.g., Ruff et al., New titanium compounds,Berichte der Deutschen Chemischen Gesellschaft, 1912, 45, pp. 1364-1373;

R. Höltje, Zeitschrift fuer Anorganische und Allgemeine Chemie, 1930,190, pp 241-256;

Emeléus et al., Complexes of Titanium and Zirconium Halides with OrganicLigands, J. Chemical Society (Resumed), 1958, pp. 4245-50;

Fowles et al., Journal of Chemical Society (Resumed), 1959 pp. 990-997;

G. W. A. Fowles et al., The Reaction of Titanium Halides with TertiaryAmines, Journal of Chemical Society (Resumed), 1963, pp. 33-38;

Baker et al., Sulphur Complexes of Quadrivalent Titanium, Journal of theLess-Common Metals, 1964, pp. 47-50;

Eric Turin et al., Adducts of Titanium Tetrahalides with Neutral LewisBases. Part I. Structure and Stability: a Vibrational and MultinuclearNMR Study, Inorganica Chimica Acta, 134 (1987) pp. 67-78;

U.S. Pat. No. 5,656,338 to Gordon discloses chemical vapor deposition oftitanium metal by forming a liquid solution of titanium tetrabromide inbromine, vaporizing the solution and contacting the vapor mixture withplasma in the vicinity of the substrate;

U.S. Pat. No. 6,706,115 to Leskela et al. discloses methods forproducing metal nitride thin layers have low resistivity by means ofatomic layer deposition processes comprising alternate surface reactionsof metal and nitrogen source materials; and

U.S. Pat. App. Pub. No. 2010/0104755 to Dussarrat et al. disclosesmethods for producing a metal-containing film by introducing a metalsource which does not contain metal-C or metal-N—C s-bonds, a siliconprecursor, a nitrogen precursor, a carbon source and a reducing agentinto a CVD chamber and reacting same at the surface of a substrate toproduce a metal containing film in a single step.

Synthesis and characterization of a variety of mixed titanium haloalkylamino derivatives is also known. See, e.g., Von Hans Bürger et al.,Dialkylamino-titanbromide, Zeitschrift for anorganishce und allgemeineChemie, Band 370, 1969, pp. 275-282;

Von Hans Bürger et al., Dialkylamido-titaniodide, Zeitschrift foranorganishce und allgemeine Chemie, Band 381, 1971, pp. 198-204;

US Pat App Pub No. 2005/0042888 to Roder et al. discloses metalorganicprecursors of the formula (R₁R₂N)_(a-b)MX_(b), wherein M is theprecursor metal center, selected form the group of Ta, Ti, W, Nb, Si,Al, and B; a is a number equal to the valence of M; 1≤b≤(a−1); R₁ and R₂can be the same as or different from one another and are eachindependently selected from the group of H, C1-C4 alkyl, C3-C6cycloalkyl, and R^(o) ₃Si, where each R^(o) can be the same or differentand each R^(o) is independently selected from H and C1-C4 alkyl; and Xis selected from the group of chlorine, fluorine, bromine and iodine.

FR Pat. App. Pub. No. 2871292 to Dussarrat discloses injection of ametallic precursor having the formula MX₄ or MX₅, wherein M ispreferably Hf, an oxidant and of tetrakis(ethylamino)silane undertemperature and pressure conditions that improve the reactivity of thesilicon source.

A need remains for thermally stable, volatile, and preferably liquidTi-containing precursors capable of providing controlled film thicknessduring vapor phase deposition at high temperature.

SUMMARY

Ti-containing film forming compositions are disclosed comprising Tihalide-containing precursors having one of the following formula:

TiX_(b):A_(c)

with b=3 or 4; c=1-3; X=Br or I; A=SR₂, SeR₂, TeR₂, or PR₃, and each Ris independently H or a C1-C10 hydrocarbon.

Also disclosed are Ti-containing film forming compositions comprising Tihalide-containing precursors having one of the following formula:

Ti(NR′₂)_(y)(X)_(z)

Ti(—N—R″—N—)_(y)(X)_(z)

with y=1-3; z=1-3; y+z=4; X=Br or I; each R′ independently a C1-C5hydrocarbon or SiR′″₃, with each R′″ independently being H or a C1-C5hydrocarbon; and R″=a C1-C5 hydrocarbon.

Any of the disclosed Ti-containing film forming compositions may furtherinclude one or more of the following aspects:

-   -   each R independently being a C1-C5 hydrocarbon;    -   each R being a different C1-C5 hydrocarbon;    -   A=SRR′, SeRR′, TeRR′, or PRR′R″, with each R, R′, and R″═H or a        C1-C10 hydrocarbon, provided that R does not equal R′ or R″;    -   b=4 when c=1 or 2;    -   b=3 when c=3;    -   the Ti halide-containing precursor having a melting point lower        than the melting point of the analogous TiX₄ compound;    -   X is Br;    -   the Ti halide-containing precursor having a melting point        between approximately −50° C. and approximately 39° C. at        standard pressure;    -   X is 1;    -   the Ti halide-containing precursor having a melting point        between approximately −50° C. and approximately 150° C. at        standard pressure;    -   the Ti halide-containing precursor having a melting point        between approximately −50° C. and approximately 30° C. at        standard pressure;    -   the Ti halide-containing precursor being a liquid at standard        temperature and pressure;    -   A is SR₂, with each R independently a C1-C5 hydrocarbon;    -   A is SRR′, with R and R′ independently a C1-C5 hydrocarbon,        provided that R does not equal R′;    -   A is SPr₂;    -   A is SBu₂;    -   A is SEtPr;    -   A is tetrahydrothiophene;    -   A=SR₂, c=1, and each R is independently a C3-C5 hydrocarbon;    -   A=SR₂, c=2, and each R is independently a C1-2 hydrocarbon;    -   A=tetrahydrothiophene and c=2;    -   the Ti halide-containing precursor being TiBr₄:SEt(nPr);    -   the Ti halide-containing precursor being TiBr₄:S(nPr)₂;    -   the Ti halide-containing precursor being TiBr₄:S(iPr)₂;    -   the Ti halide-containing precursor being TiBr₄:SBu₂;    -   the Ti halide-containing precursor being TiBr₄:S(nBu)₂;    -   the Ti halide-containing precursor being TiBr₄:S(tBu)₂;    -   the Ti halide-containing precursor being TiBr₄:S(iBu)₂;    -   the Ti halide-containing precursor being TiBr₄:S(sBu)₂;    -   the Ti halide-containing precursor being TiBr₄:(SEt₂)₂;    -   the Ti halide-containing precursor being TiBr₄:(SMe₂)₂;    -   the Ti halide-containing precursor being TiBr₄:(SMeEt)₂;    -   the Ti halide-containing precursor being        TiBr₄:(tetrahydrothiophene)₂;    -   the Ti halide-containing precursor being TiI₄:SEt(nPr);    -   the Ti halide-containing precursor being TiI₄:S(nPr)₂;    -   the Ti halide-containing precursor being TiI₄:S(iPr)₂;    -   the Ti halide-containing precursor being TiI₄:SBu₂;    -   the Ti halide-containing precursor being TiI₄:S(nBu)₂;    -   the Ti halide-containing precursor being TiI₄:S(tBu)₂;    -   the Ti halide-containing precursor being TiI₄:S(iBu)₂;    -   the Ti halide-containing precursor being TiI₄:S(sBu)₂;    -   the Ti halide-containing precursor being TiI₄:(SEt₂)₂;    -   the Ti halide-containing precursor being TiI₄:(SMe₂)₂;    -   the Ti halide-containing precursor being TiI₄:(SMeEt)₂;    -   the Ti halide-containing precursor being        TiI₄:(tetrahydrothiophene)₂;    -   A is SeR₂, with each R independently a C1-C5 hydrocarbon;    -   A is SeR₂, with each R being a different C1-C5 hydrocarbon;    -   A is SePr₂;    -   A is SeBu₂;    -   A is SeEtPr;    -   A is tetrahydroselenophene;    -   A=SeR₂, c=1, and each R is independently a C3-C5 hydrocarbon;    -   A=SeR₂, c=2, and each R is independently a C1-2 hydrocarbon;    -   A=tetrahydroselenophene and c=2;    -   the Ti halide-containing precursor being TiBr₄:SeEtPr    -   the Ti halide-containing precursor being TiBr₄:SePr₂;    -   the Ti halide-containing precursor being TiBr₄:SeBu₂;    -   the Ti halide-containing precursor being TiBr₄:(SeMe₂)₂;    -   the Ti halide-containing precursor being TiBr₄:(SeEt₂)₂;    -   the Ti halide-containing precursor being TiBr₄:(SeMeEt)₂;    -   the Ti halide-containing precursor being        TiBr₄:(tetrahydroselenophene)₂;    -   the Ti halide-containing precursor being TiI₄:SeEtPr;    -   the Ti halide-containing precursor being TiI₄:SePr₂;    -   the Ti halide-containing precursor being TiI₄:SeBu₂;    -   the Ti halide-containing precursor being TiI₄:(SeMe₂)₂;    -   the Ti halide-containing precursor being TiI₄:(SeEt₂)₂;    -   the Ti halide-containing precursor being TiI₄:(SeMeEt)₂;    -   the Ti halide-containing precursor being        TiI₄:(tetrahydroselenophene)₂;    -   L is TeR₂, with each R independently a C1-C5 hydrocarbon;    -   L is TeR₂, with each R being a different C1-C5 hydrocarbon;    -   A is TePr₂;    -   A is TeBu₂;    -   A is EtPr;    -   A is tetrahydrotellurophene;    -   A=TeR₂, c=1, with each R independently a C3-C5 hydrocarbon;    -   A=TeR₂, c=2, with each R independently a C1-2 hydrocarbon;    -   A=tetrahydrotellurophene and c=2;    -   the Ti halide-containing precursor being TiBr₄:TeEtPr    -   the Ti halide-containing precursor being TiBr₄:TePr₂;    -   the Ti halide-containing precursor being TiBr₄:TeBu₂;    -   the Ti halide-containing precursor being TiBr₄:(TeMe₂)₂;    -   the Ti halide-containing precursor being TiBr₄:(TeEt₂)₂;    -   the Ti halide-containing precursor being TiBr₄:(TeMeEt)₂;    -   the Ti halide-containing precursor being        TiBr₄:(tetrahydrotellurophene)₂;    -   the Ti halide-containing precursor being TiI₄:TeEtPr,    -   the Ti halide-containing precursor being TiI₄:TePr₂;    -   the Ti halide-containing precursor being TiI₄:TeBu₂;    -   the Ti halide-containing precursor being TiI₄:(TeMe₂)₂;    -   the Ti halide-containing precursor being TiI₄:(TeEt₂)₂;    -   the Ti halide-containing precursor being TiI₄:(TeMeEt)₂;    -   the Ti halide-containing precursor being        TiI₄:(tetrahydrotellurophene)₂;    -   A is PR₃, with each R independently H or a C1-C5 hydrocarbon;    -   A is PRR′R″, with R, R′, and R″ H or a C1-C5 hydrocarbon,        provided that R does not equal R′ or R″;    -   the Ti halide-containing precursor being TiBr₄:PR₃, with each R        independently H or a C3-C10 hydrocarbon;    -   the Ti halide-containing precursor being TiBr₄:PH₃;    -   the Ti halide-containing precursor being TiBr₄:(PR₃)₂, with each        R independently H or a C1-2 hydrocarbon;    -   the Ti halide-containing precursor being TiBr₄:(PH₃)₂;    -   the Ti halide-containing precursor being TiBr₃:(PR₃)₃, with each        R independently H or a C1-2 hydrocarbon;    -   the Ti halide-containing precursor being TiBr₃:(PH₃)₃;    -   the Ti halide-containing precursor being        TiBr₄:(R₂P—(CH₂)_(n)—PR₂), with each R independently a C1-5        hydrocarbon and n=1-4;    -   the Ti halide-containing precursor being        TiBr₄:(Me₂P—(CH₂)_(n)—PMe₂);    -   the Ti halide-containing precursor being        TiBr₄:(EtMeP—(CH₂)_(n)—PMeEt);    -   the Ti halide-containing precursor being        TiBr₄:(Et₂P—(CH₂)_(n)-PEt₂);    -   the Ti halide-containing precursor being        TiBr₄:(iPr₂P—(CH₂)_(n)-PiPr₂);    -   the Ti halide-containing precursor being        TiBr₄:(HiPrP-(CH₂)_(n)-PHiPr);    -   the Ti halide-containing precursor being        TiBr₄:(tBu₂P—(CH₂)_(n)-PtBu₂);    -   the Ti halide-containing precursor being        TiBr₄:(tBuHP-(CH₂)_(n)-PHtBu);    -   the Ti halide-containing precursor being        TiBr₄:(tAmHP-(CH₂)_(n)-PHtAm);    -   the Ti halide-containing precursor being        TiBr₄:(Me₂P—(CH₂)—PMe₂);    -   the Ti halide-containing precursor being        TiBr₄:(EtMeP—(CH₂)—PMeEt);    -   the Ti halide-containing precursor being        TiBr₄:(Et₂P—(CH₂)-PEt₂);    -   the Ti halide-containing precursor being        TiBr₄:(iPr₂P—(CH₂)-PiPr₂);    -   the Ti halide-containing precursor being        TiBr₄:(HiPrP-(CH₂)-PHiPr);    -   the Ti halide-containing precursor being        TiBr₄:(tBu₂P—(CH₂)-PtBu₂);    -   the Ti halide-containing precursor being        TiBr₄:(tBuHP-(CH₂)-PHtBu);    -   the Ti halide-containing precursor being        TiBr₄:(tAmHP-(CH₂)-PHtAm);    -   the Ti halide-containing precursor being        TiBr₄:(Me₂P—(CH₂)₂—PMe₂);    -   the Ti halide-containing precursor being        TiBr₄:(EtMeP—(CH₂)₂—PMeEt);    -   the Ti halide-containing precursor being        TiBr₄:(Et₂P—(CH₂)₂-PEt₂);    -   the Ti halide-containing precursor being        TiBr₄:(iPr₂P—(CH₂)₂-PiPr₂);    -   the Ti halide-containing precursor being        TiBr₄:(HiPrP-(CH₂)₂-PHiPr);    -   the Ti halide-containing precursor being        TiBr₄:(tBU₂P—(CH₂)₂-PtBu₂);    -   the Ti halide-containing precursor being        TiBr₄:(tBuHP-(CH₂)₂-PHtBu);    -   the Ti halide-containing precursor being        TiBr₄:(tAmHP-(CH₂)₂-PHtAm);    -   the Ti halide-containing precursor being        TiI₄:(Me₂P—(CH₂)_(n)—PMe₂);    -   the Ti halide-containing precursor being        TiI₄:(EtMeP—(CH₂)_(n)—PMeEt);    -   the Ti halide-containing precursor being        TiI₄:(Et₂P—(CH₂)_(n)-PEt₂);    -   the Ti halide-containing precursor being        TiI₄:(iPr₂P—(CH₂)_(n)-PiPr₂);    -   the Ti halide-containing precursor being        TiI₄:(HiPrP-(CH₂)_(n)-PHiPr);    -   the Ti halide-containing precursor being        TiI₄:(tBu₂P—(CH₂)_(n)-PtBu₂);    -   the Ti halide-containing precursor being        TiI₄:(tBuHP-(CH₂)_(n)-PHtBu);    -   the Ti halide-containing precursor being        TiI₄:(tAmHP-(CH₂)_(n)-PHtAm);    -   the Ti halide-containing precursor being TiI₄:(Me₂P—(CH₂)—PMe₂);    -   the Ti halide-containing precursor being        TiI₄:(EtMeP—(CH₂)—PMeEt);    -   the Ti halide-containing precursor being TiI₄:(Et₂P—(CH₂)-PEt₂);    -   the Ti halide-containing precursor being        TiI₄:(iPr₂P—(CH₂)-PiPr₂);    -   the Ti halide-containing precursor being        TiI₄:(HiPrP-(CH₂)-PHiPr);    -   the Ti halide-containing precursor being        TiI₄:(tBU₂P—(CH₂)-PtBu₂);    -   the Ti halide-containing precursor being        TiI₄:(tBuHP-(CH₂)-PHtBu);    -   the Ti halide-containing precursor being        TiI₄:(tAmHP-(CH₂)-PHtAm);    -   the Ti halide-containing precursor being        TiI₄:(Me₂P—(CH₂)₂—PMe₂);    -   the Ti halide-containing precursor being        TiI₄:(EtMeP—(CH₂)₂—PMeEt);    -   the Ti halide-containing precursor being        TiI₄:(Et₂P—(CH₂)₂-PEt₂);    -   the Ti halide-containing precursor being        TiI₄:(iPr₂P—(CH₂)₂-PiPr₂);    -   the Ti halide-containing precursor being        TiI₄:(HiPrP-(CH₂)₂-PHiPr);    -   the Ti halide-containing precursor being        TiI₄:(tBu₂P—(CH₂)₂-PtBu₂);    -   the Ti halide-containing precursor being        TiI₄:(tBuHP-(CH₂)₂-PHtBu);    -   the Ti halide-containing precursor being        TiI₄:(tAmHP-(CH₂)₂-PHtAm);    -   the Ti halide-containing precursor being        TiBr₃:(R₂P—(CH₂)_(n)—PR₂), with each R independently a C1-5        hydrocarbon and n=1-4;    -   the Ti halide-containing precursor being        TiBr₃:(Me₂P—(CH₂)_(n)—PMe₂);    -   the Ti halide-containing precursor being        TiBr₃:(EtMeP—(CH₂)_(n)—PMeEt);    -   the Ti halide-containing precursor being        TiBr₃:(Et₂P—(CH₂)_(n)-PEt₂);    -   the Ti halide-containing precursor being        TiBr₃:(iPr₂P—(CH₂)_(n)-PiPr₂);    -   the Ti halide-containing precursor being        TiBr₃:(HiPrP-(CH₂)_(n)-PHiPr);    -   the Ti halide-containing precursor being        TiBr₃:(tBu₂P—(CH₂)_(n)—PtB₂);    -   the Ti halide-containing precursor being        TiBr₃:(tBuHP-(CH₂)_(n)-PHtBu);    -   the Ti halide-containing precursor being        TiBr₃:(tAmHP-(CH₂)_(n)-PHtAm);    -   the Ti halide-containing precursor being        TiBr₃:(Me₂P—(CH₂)—PMe₂);    -   the Ti halide-containing precursor being        TiBr₃:(EtMeP—(CH₂)—PMeEt);    -   the Ti halide-containing precursor being        TiBr₃:(Et₂P—(CH₂)-PEt₂);    -   the Ti halide-containing precursor being        TiBr₃:(iPr₂P—(CH₂)-PiPr₂);    -   the Ti halide-containing precursor being        TiBr₃:(HiPrP-(CH₂)-PHiPr);    -   the Ti halide-containing precursor being        TiBr₃:(tBu₂P—(CH₂)-PtBu₂);    -   the Ti halide-containing precursor being        TiBr₃:(tBuHP-(CH₂)-PHtBu);    -   the Ti halide-containing precursor being        TiBr₃:(tAmHP-(CH₂)-PHtAm);    -   the Ti halide-containing precursor being        TiBr₃:(Me₂P—(CH₂)₂—PMe₂);    -   the Ti halide-containing precursor being        TiBr₃:(EtMeP—(CH₂)₂—PMeEt);    -   the Ti halide-containing precursor being        TiBr₃:(Et₂P—(CH₂)₂-PEt₂);    -   the Ti halide-containing precursor being        TiBr₃:(iPr₂P—(CH₂)₂-PiPr₂);    -   the Ti halide-containing precursor being        TiBr₃:(HiPrP-(CH₂)₂-PHiPr);    -   the Ti halide-containing precursor being        TiBr₃:(tBu₂P—(CH₂)₂-PtBu₂);    -   the Ti halide-containing precursor being        TiBr₃:(tBuHP-(CH₂)₂-PHtBu);    -   the Ti halide-containing precursor being        TiBr₃:(tAmHP-(CH₂)₂-PHtAm);    -   the Ti halide-containing precursor being        TiI₃:(Me₂P—(CH₂)_(n)—PMe₂);    -   the Ti halide-containing precursor being        TiI₃:(EtMeP—(CH₂)_(n)—PMeEt);    -   the Ti halide-containing precursor being        TiI₃:(Et₂P—(CH₂)_(n)-PEt₂);    -   the Ti halide-containing precursor being        TiI₃:(iPr₂P—(CH₂)_(n)-PiPr₂);    -   the Ti halide-containing precursor being        TiI₃:(HiPrP-(CH₂)_(n)-PHiPr);    -   the Ti halide-containing precursor being        TiI₃:(tBU₂P—(CH₂)_(n)-PtBu₂);    -   the Ti halide-containing precursor being        TiI₃:(tBuHP-(CH₂)_(n)-PHtBu);    -   the Ti halide-containing precursor being        TiI₃:(tAmHP-(CH₂)_(n)-PHtAm);    -   the Ti halide-containing precursor being TiI₃:(Me₂P—(CH₂)—PMe₂);    -   the Ti halide-containing precursor being        TiI₃:(EtMeP—(CH₂)—PMeEt);    -   the Ti halide-containing precursor being TiI₃:(Et₂P—(CH₂)-PEt₂);    -   the Ti halide-containing precursor being        TiI₃:(iPr₂P—(CH₂)-PiPr₂);    -   the Ti halide-containing precursor being        TiI₃:(HiPrP-(CH₂)-PHiPr);    -   the Ti halide-containing precursor being        TiI₃:(tBu₂P—(CH₂)-PtBu₂);    -   the Ti halide-containing precursor being        TiI₃:(tBuHP-(CH₂)-PHtBu);    -   the Ti halide-containing precursor being        TiI₃:(tAmHP-(CH₂)-PHtAm);    -   the Ti halide-containing precursor being        TiI₃:(Me₂P—(CH₂)₂—PMe₂);    -   the Ti halide-containing precursor being        TiI₃:(EtMeP—(CH₂)₂—PMeEt);    -   the Ti halide-containing precursor being        TiI₃:(Et₂P—(CH₂)₂-PEt₂);    -   the Ti halide-containing precursor being        TiI₃:(iPr₂P—(CH₂)₂-PiPr₂);    -   the Ti halide-containing precursor being        TiI₃:(HiPrP-(CH₂)₂-PHiPr);    -   the Ti halide-containing precursor being        TiI₃:(tBU₂P—(CH₂)₂-PtBu₂);    -   the Ti halide-containing precursor being        TiI₃:(tBuHP-(CH₂)₂-PHtBu);    -   the Ti halide-containing precursor being        TiI₃:(tAmHP-(CH₂)₂-PHtAm);    -   A is R(═O)Cl, with R being a C2-C4 hydrocarbon;    -   the Ti halide-containing precursor being TiBr₄:R(═O)Cl, with R        being a C2-C10 hydrocarbon;    -   the Ti halide-containing precursor being TiBr₄:(Me-C(═O)Cl);    -   the Ti halide-containing precursor being TiBr₄:(Ph-C(═O)Cl);    -   the Ti halide-containing precursor being TiI₄:(Me-C(═O)Cl);    -   A is RNO₂, with R being a C1-C5 hydrocarbon;    -   the Ti halide-containing precursor being TiBr₄:(MeNO₂);    -   the Ti halide-containing precursor being TiI₄:(MeNO₂);    -   the Ti halide-containing precursor being TiBr₄:(EtNO₂);    -   the Ti halide-containing precursor being TiBr₄:(PrNO₂);    -   the Ti halide-containing precursor being TiBr₄:(PhNO₂);    -   A is R═N, with R being a C2-C6 hydrocarbon;    -   the Ti halide-containing precursor being TiBr₄:(Me-C≡N)₂;    -   the Ti halide-containing precursor being TiBr₄:(Et-C≡N)₂;    -   the Ti halide-containing precursor being TiBr₄:(Pr—C≡N)₂;    -   the Ti halide-containing precursor being TiBr₄:(Bu-C≡N)₂;    -   the Ti halide-containing precursor being TiBr₄:(Ph-C≡N)₂;    -   A is pyridine;    -   A is piperidine;    -   the Ti halide-containing precursor being TiBr₄:pyridine;    -   the Ti halide-containing precursor being TiBr₄:piperidine;    -   the Ti halide-containing precursor being        TiBr₄:2,2,6,6-tetramethylpiperidine;    -   the Ti halide-containing precursor being TiX₃(NR₂);    -   the Ti halide-containing precursor being TiBr₃(NR₂);    -   the Ti halide-containing precursor being TiBr₃(NEt₂);    -   the Ti halide-containing precursor being TiBr₃(pyrrolidine);    -   the Ti halide-containing precursor being TiBr₃(pyridine);    -   the Ti halide-containing precursor being TiBr₃(piperidine);    -   the Ti halide-containing precursor being TiI₃(NR₂);    -   the Ti halide-containing precursor being TiX₂(NR₂)₂;    -   the Ti halide-containing precursor being TiBr₂(NR₂)₂;    -   the Ti halide-containing precursor being TiBr₂(NMe₂)₂;    -   the Ti halide-containing precursor being TiI₂(NR₂)₂;    -   the Ti halide-containing precursor being TiX(NR₂)₃;    -   the Ti halide-containing precursor being TiBr(NR₂)₃;    -   the Ti halide-containing precursor being TiI(NR₂)₃;    -   the Ti halide-containing precursor being TiX₃(N^(R,R′)-fmd),        with R and R′ independently being a C1-C5 hydrocarbon;    -   the Ti halide-containing precursor being TiBr₃(N^(iPr)-fmd);    -   the Ti halide-containing precursor being TiI₃(N^(iPr)-fmd);    -   the Ti halide-containing precursor being TiX₃(N^(R, R′)-amd),        with R, R′, and R″ independently being a C1-C5 hydrocarbon;    -   the Ti halide-containing precursor being TiBr₃(N^(F) Me-amd);    -   the Ti halide-containing precursor being TiI₃(N^(Fr) Me-amd);    -   the Ti halide-containing precursor being TiBr₂(—N(R)—C₂H₄—N(R)—)        with each R independently being a C1-C5 hydrocarbon;    -   the Ti halide-containing precursor being        TilBr₂(—N(R)—C₂H₄—N(R)—) with each R independently being a C1-C5        hydrocarbon;    -   the Ti-containing film forming compositions comprising between        approximately 0.1 molar % and approximately 50 molar % of the        titanium halide-containing precursors;    -   the Ti-containing film forming composition having a viscosity        between approximately 1 and approximately 50 cps;    -   the Ti-containing film forming composition having a viscosity,        between approximately 1 and approximately 20 cps;    -   the Ti-containing film forming composition comprising between        approximately 95% w/w to approximately 100% w/w of the titanium        halide-containing precursors;    -   the Ti-containing film forming composition comprising between        approximately 99% w/w to approximately 100% w/w of the titanium        halide-containing precursors;    -   the Ti-containing film forming composition further comprising a        solvent;    -   the Ti-containing film forming composition comprising between        approximately 0% w/w and 10% w/w of a hydrocarbon solvent or of        free adduct;    -   the Ti-containing film forming composition comprising between        approximately 0% w/w and 5% w/w of a hydrocarbon solvent or of        free adduct;    -   the Ti-containing film forming composition comprising between        approximately 0% w/w and 5 ppm of H₂O;    -   the Ti-containing film forming composition comprising between        approximately 0% w/w and 0.2% w/w of a mixture of oxybromide        (TiBr₂(═O)), hydroxybromide (TiBr₃(OH)), and oxides (TiO₂);    -   the Ti-containing film forming composition comprising between        approximately 0% w/w and 0.1% w/w of a mixture of oxybromide        (TiBr₂(═O)), hydroxybromide (TiBr₃(OH)), and oxides (TiO₂);    -   the Ti-containing film forming composition comprising between        approximately 0% w/w and 0.2% w/w of a mixture of oxyiodide        (TiI₂(═O)), hydroxyiodide (TiI₃(OH)), and oxides (TiO₂);    -   the Ti-containing film forming composition comprising between        approximately 0% w/w and 0.1% w/w of a mixture of oxyiodide        (TiI₂(═O)), hydroxyiodide (TiI₃(OH)), and oxides (TiO₂);    -   the Ti-containing film forming composition comprising between        approximately 0% w/w and 0.1% w/w of hydrogen bromide (HBr);    -   the Ti-containing film forming composition comprising between        approximately 0% w/w and 0.1% w/w of hydrogen iodide (HI);    -   the Ti-containing film forming composition comprising between        approximately 0% w/w and 0.2% w/w of TiX₄:SR′₂, wherein R′≠R;    -   the solvent being selected from the group consisting of C1-C16        hydrocarbons, whether saturated or unsaturated, ketones, ethers,        glymes, esters, tetrahydrofuran (THF), dimethyl oxalate (DMO),        and combinations thereof;    -   the solvent being a C1-C16 hydrocarbon;    -   the solvent being a C1-C16 halogenated hydrocarbon;    -   the solvent being tetrahydrofuran (THF);    -   the solvent being DMO;    -   the solvent being an ether;    -   the solvent being a glyme; or    -   the difference between the boiling point of the Ti        halide-containing precursor and the solvent being less than 100°        C.

Also disclosed are Ti-containing film forming compositions deliverydevices comprising a canister having an inlet conduit and an outletconduit and containing any of the Ti-containing film formingcompositions disclosed above. The disclosed delivery devices may includeone or more of the following aspects:

-   -   the Ti-containing film forming composition having a total        concentration of metal contaminants of less than 10 ppmw;    -   an end of the inlet conduit located above a surface of the        Ti-containing film forming composition and an end of the outlet        conduit located above the surface of the Ti-containing film        forming composition;    -   an end of the inlet conduit located above a surface of the        Ti-containing film forming composition and an end of the outlet        conduit located below the surface of the Ti-containing film        forming composition;    -   an end of the inlet conduit located below a surface of the        Ti-containing film forming composition and an end of the outlet        conduit located above the surface of the Ti-containing film        forming composition; or    -   the titanium halide-containing precursor being TiBr₄:S(nPr)₂.

Also disclosed are processes for the deposition of Ti-containing filmson one or more substrates. At least one Ti-containing film formingcomposition disclosed above is introduced into a reactor having at leastone substrate disposed therein. At least part of the titaniumhalide-containing precursor is deposited onto the substrate(s) to formthe Ti-containing film. The disclosed processes may further include oneor more of the following aspects:

-   -   introducing at least one reactant into the reactor;    -   the reactant being plasma-treated;    -   the reactant being remote plasma-treated;    -   the reactant not being plasma-treated;    -   the reactant being selected from the group consisting of H₂,        NH₃, hydrazines (such as N₂H₄, MeHNNH₂, MeHNNHMe), organic        amines (such as NMeH₂, NEtH₂, NMe₂H, NEt₂H, NMe₃, NEt₃, cyclic        amines like pyrrolidine or pyrimidine), nitriles (such as        acetonitrile), diamines (such as ethylene diamine,        dimethylethylene diamine, tetramethylethylene diamine),        aminoalcohols (such as ethanolamine [HO—CH₂—CH₂—NH₂], bis        ethanolamine [HN(C₂H₅OH)₂] or tris ethanolamine[N(C₂HOH)₃]),        pyrazoline, and pyridine;    -   the reactant being selected from the group consisting of        (SiH₃)₃N; N(SiH_(x)R_(3-x))₃, with each x independently 1-3 and        each R independently alkyl or NR′₂, with each R′ independently H        or C1-C4 alkyl (such as (H₃Si)₂N(SiH₂NEt₂), (H₃Si)₂N(SiH₂NiPr₂),        or (H₃Si)₂N(SiH₂iPr)); R₃Si—NH—SiR₃, with each R independently        H, Cl, Br, I, or a C1-C4 alkyl group (such as H₃Si—NH—SiH₃,        H₂ISi—NH—SiH₃,or Me₃Si—NH—SiMe₃); hydridosilanes (such as SiH₄,        Si₂He, Si₃He, Si₄H₁₀, Si₅H₁₀, Si₅H₁₂); chlorosilanes and        chloropolysilanes (such as SiHCl₃, SiH₂Cl₂, SiH₃Cl, Si₂Cl₆,        Si₂HCl₅, Si₃Cl₈); bromosilanes and bromopolysilanes (such as        SiHBr₃, SiH₂Br₂, SiH₃Br, Si₂Br₆, Si₂HBr₅, Si₃Br₈); iodosilanes        and iodopolysilanes (such as SiHI₃, SiH₂I₂, SiH₃I, Si₂I₆,        Si₂HI₅, Si₃I₈); alkylsilanes (such as Me₂SiH₂, Et₂SiH₂, MeSiH₃,        EtSiH₃); and aminosilanes (such as tris(dimethylamino)silane,        bis(diethylamino)silane, di-isopropylaminosilane and other mono,        bis or tris aminosilanes); radicals thereof; or mixtures thereof    -   the reactant being selected from the group consisting of NH₃,        N(SiH₃)₃, aminosilanes, and mixtures thereof;    -   the reactant being selected from trialkylaluminum,        dialkylaluminum halide, alkylaluminum halide, alkylamino and        alkoxy derivatives of aluminum, alanes, amine-adducted alanes,        and mixtures thereof;    -   the reactant being NH₃;    -   the reactant being selected from the group consisting of: O₂,        O₃, H₂O, H₂O₂, NO, N₂O, NO₂, an alcohol, a diol (such as        ethylene glycol), plasma activated oxygen radicals thereof, and        mixtures thereof;    -   the reactant being H₂O;    -   the reactant being O₂;    -   the reactant being plasma treated O₂;    -   the reactant being O₃;    -   the reactant being selected from the group consisting of NH₃,        hydrazine and substituted hydrazines, amines such as primary        amines (methylamine, ethylamine, isopropylamine,        tertbutylamine), secondary amines (such as dimethylamine,        diethylamine, ethylmethylamine, di-isopropylamine, pyrrolidine),        or tertiary amines (such as triethylamine (TEA), trimethylamine        (TMA));    -   the reactant being NH₃;    -   the reactant being hydrazine or substituted hydrazines;    -   the reactant being primary amines, such as methylamine,        ethylamine, isopropylamine, tertbutylamine;    -   the reactant being secondary amines, such as dimethylamine,        diethylamine, ethylmethylamine, bis-isopropylamine, pyrrolidine;    -   the reactant being tertiary amines, such as TEA, TMA;    -   the reactant being a Si-containing precursor;    -   the Si-containing precursor being selected from the group        consisting of SiH₄, Si₂He, Si₄H₈, trisilylamine (TSA), and        substituted TSA (substituted by alkyl, dialkylamine, halide);    -   the Si-containing precursor being TSA;    -   the Ti-containing film forming composition and the reactant        being introduced into the reactor simultaneously;    -   the reactor being configured for chemical vapor deposition;    -   the reactor being configured for plasma enhanced chemical vapor        deposition;    -   the Ti-containing film forming composition and the reactant        being introduced into the chamber sequentially;    -   the reactor being configured for atomic layer deposition;    -   the reactor being configured for plasma enhanced atomic layer        deposition;    -   the reactor being configured for spatial atomic layer        deposition;    -   liberating the adduct A from the Ti halide-containing precursor,    -   the liberated adduct A forming a blocking agent;    -   introducing a blocking agent into the reactor;    -   the blocking agent being a self-assembling monolayer;    -   the blocking agent being an inhibitor;    -   the Ti-containing film being a titanium oxide (Ti_(n)O_(m),        wherein each n and m is an integer which inclusively range from        1 to 6);    -   the Ti-containing film being TiO₂;    -   the Ti-containing film being TiN;    -   the Ti-containing film being TiSiN;    -   the Ti-containing film being TiM_(i)O_(x), wherein i ranges from        0 to 1; x ranges from 1 to 6; and M is any element from the        Periodic table;    -   the Ti-containing film being TiM_(i)O_(x), wherein i ranges from        0 to 1; x ranges from 1 to 6; and M is Si, Al, or Ge;    -   the Ti-containing film being TiM_(i)N_(y), wherein i ranges from        0 to 1; y ranges from 0.5 to 6; and M is any element from the        Periodic table;    -   the Ti-containing film being TiM_(i)N_(y), wherein i ranges from        0 to 1; y ranges from 0.5 to 6; and M is Si, Al, or Ge;    -   the Ti-containing film being TiCN;    -   the Ti-containing film being TiAl;    -   the Ti-containing film being TiAlN;    -   the Ti-containing film being TiM_(i)N_(y)O_(x), wherein i ranges        from 0 to 1; x and y range from 1 to 6; and M is any element        from the Periodic table;    -   the Ti-containing film being TiM_(i)N_(y)O_(x), wherein i ranges        from 0 to 1; x and y range from 1 to 6; and M is Si, Al, or Ge;    -   the Ti-containing film having a C concentration ranging from        approximately 0 at % to 5 at %;    -   the Ti-containing film having a O concentration ranging from        approximately 0 at % to 40 at %;    -   the Ti-containing film having a S concentration ranging from        approximately 0 at % to 2 at %;    -   the Ti-containing film having a Se concentration ranging from        approximately 0 at % to 2 at %;    -   the Ti-containing film having a Te concentration ranging from        approximately 0 at % to 2 at %;    -   the Ti-containing film having a P concentration ranging from        approximately 0 at % to 2 at %;    -   the TiN-containing film forming an electrode in a capacitor        structure;    -   the TiN-containing film forming a metal gate in a CMOS        transistor or Flash memory;    -   the TiN-containing film forming a buried word line;    -   the Ti-containing film being a titanium silicide contact layer        between conductive metal plugs and the underlying doped silicon        layer in a CMOS transistor or Flash memory;    -   the Ti-containing film being selectively deposited onto a doped        silicon layer but not a conductive metal plug; or    -   the Ti-containing film being a titanium nitride layer        selectively deposited on a tungsten layer to form a buried word        line.

Notation and Nomenclature

Certain abbreviations, symbols, and terms are used throughout thefollowing description and claims, and include:

As used herein, the indefinite article “a” or “an” means one or more.

As used herein, the terms “approximately” or “about” mean±10% of thevalue stated.

As used herein, the term “independently” when used in the context ofdescribing R groups should be understood to denote that the subject Rgroup is not only independently selected relative to other R groupsbearing the same or different subscripts or superscripts, but is alsoindependently selected relative to any additional species of that same Rgroup. For example in the formula MR¹ _(x) (NR²R³)_((4-x)), where x is 2or 3, the two or three R¹ groups may, but need not be identical to eachother or to R² or to R³. Further, it should be understood that unlessspecifically stated otherwise, values of R groups are independent ofeach other when used in different formulas.

As used herein, the term “adduct” means a molecular entity which isformed by direct combination of two separate molecule entities in such away there is connectivity but no loss of atoms; the term “Lewis acid”means a molecular entity that is an electron-pair acceptor; the term“Lewis base” means a molecular entity able to provide a pair ofelectrons and thus coordinate to a Lewis acid; and the term “Lewisadduct” means an adduct formed between a Lewis acid and a Lewis base.

As used herein, the term “hydrocarbyl group” refers to a functionalgroup containing carbon and hydrogen; the term “alkyl group” refers tosaturated functional groups containing exclusively carbon and hydrogenatoms. The hydrocarbyl group may be saturated or unsaturated. Eitherterm refers to linear, branched, or cyclic groups. Examples of linearalkyl groups include without limitation, methyl groups, ethyl groups,propyl groups, butyl groups, etc. Examples of branched alkyls groupsinclude without limitation, t-butyl. Examples of cyclic alkyl groupsinclude without limitation, cyclopropyl groups, cyclopentyl groups,cyclohexyl groups, etc.

As used herein, the abbreviation “Me” refers to a methyl group; theabbreviation “Et” refers to an ethyl group; the abbreviation “Pr” refersto a propyl group; the abbreviation “nPr” refers to a “normal” or linearpropyl group; the abbreviation “iPr” refers to an isopropyl group; theabbreviation “Bu” refers to a butyl group; the abbreviation “nBu” refersto a “normal” or linear butyl group; the abbreviation “tBu” refers to atert-butyl group, also known as 1,1-dimethylethyl; the abbreviation“sBu” refers to a sec-butyl group, also known as 1-methylpropyl; theabbreviation “iBu” refers to an iso-butyl group, also known as2-methylpropyl; the term “amyl” refers to an amyl or pentyl group (i.e.,a C5 alkyl group); the term “tAmyl” refers to a tert-amyl group, alsoknown as 1,1-dimethylpropyl; the term “halide” refers to the halogenanions F⁻, Cl⁻, Br, and I⁻; and the abbreviation “TMS” refers totrimethylsilyl or —SiMe₃.

As used herein, the abbreviation “N^(R, R′) R″-amd” or N^(R) R″-amd whenR═R′ refers to the amidinate ligand [R—N—C(R″)═N—R′], wherein R, R′ andR″ are defined alkyl groups, such as Me, Et, nPr, iPr, nBu, iBi, sBu ortBu; the abbreviation “N^(R, R′)-fmd” or N^(R)-fmd when R═R′ refers tothe formidinate ligand [R—N—C(H)═N—R′], wherein R and R′ are definedalkyl groups, such as Me, Et, nPr, iPr, nBu, iBi, sBu or tBu; theabbreviation “N^(R, R′), N^(R″, R′″)-gnd” or N^(R), N^(R′)-gnd when R═R′and R″═R′″ refers to the guanidinate ligand [R—N—C(NR″R′″)═NR′], whereinR, R′, R″ and R′″ are defined alkyl group such as Me, Et, nPr, iPr, nBu,iBi, sBu or tBu. Although depicted here as having a double bond betweenthe C and N of the ligand backbone, one of ordinary skill in the artwill recognize that the amidinate, formidinate and guanidinate ligandsdo not contain a fixed double bond. Instead, one electron is delocalizedamongst the N—C—N chain.

The standard abbreviations of the elements from the periodic table ofelements are used herein. It should be understood that elements may bereferred to by these abbreviations (e.g., Ti refers to titanium, Brrefers to bromine, C refers to carbon, etc.). Additionally, Group 3refers to Group 3 of the Periodic Table (i.e., Sc, Y, La, or Ac) andGroup 5 refers to Group 5 of the Periodic Table (i.e., V, Nb, or Ta).

Any and all ranges recited herein are inclusive of their endpoints(i.e., x=1 to 4 or x ranges from 1 to 4 includes x=1, x=4, and x=anynumber in between), irrespective of whether the term “inclusively” isused.

As used herein, the term “selective” or “selectively” means to deposit afilm on one type of substrate while not depositing a film on a secondtype of substrate or to preferentially grow a film faster on one type ofsubstrate than on a second type of substrate. For example, the substratemay contain a tungsten plug or channel surrounded by a doped silicondioxide. The disclosed Ti-containing film forming composition maydeposit a Ti-containing film on the tungsten, but not on the surroundingsilicon dioxide, or vice versa. Alternatively, during the same exposureperiod, the disclosed Ti-containing film forming composition may form athicker film on one type of substrate than on another type of substrate.The thicker film may be due to a faster growth rate or shorter inductiontime. As a result, the disclosed Ti-containing film forming compositionsselectively deposit a Ti-containing film on one substrate as compared toa second substrate.

Please note that the films or layers deposited, such as titanium oxideor titanium nitride, may be listed throughout the specification andclaims without reference to their proper stoichiometry (i.e., TiO₂,Ti₃N₄). The layers may include but are not limited to pure (Ti) layers,carbide (Ti_(o)C_(p)) layers, nitride (Ti_(k)N_(l)) layers, oxide(Ti_(n)O_(m)) layers, or mixtures thereof, wherein k, l, m, n, o, and pinclusively range from 1 to 6. For instance, titanium oxide isTi_(n)O_(m), wherein n ranges from 0.5 to 1.5 and m ranges from 1.5 to3.5. More preferably, the titanium oxide layer is TiO₂. These films mayalso contain Hydrogen, typically from 0 at % to 15 at %. However, sincenot routinely measured, any film compositions given ignore their Hcontent, unless explicitly stated otherwise.

BRIEF DESCRIPTION OF THE FIGURES

For a further understanding of the nature and objects of the presentinvention, reference should be made to the following detaileddescription, taken in conjunction with the accompanying figures wherein:

FIG. 1 is a side view of one embodiment of a liquid Ti-containing filmforming composition delivery device 1;

FIG. 2 is a side view of a second embodiment of the Ti-containing filmforming composition delivery device 1;

FIG. 3 is an exemplary embodiment of a solid precursor sublimator 100for subliming solid Ti-containing film forming compositions;

FIG. 4 is the ¹H NMR spectrum of the TiBr₄:S(nPr)₂ precursor produced inExample 1;

FIG. 5 is a ThermoGravimetric Analysis/Differential Thermal Analysis(TGA/DTA) graph illustrating the percentage of weight loss (TGA) or thedifferential temperature (DTA) of TiBr₄:S(nPr)₂ upon temperatureincrease;

FIG. 6 is the ¹H NMR spectrum of the TiBr₄:SEtPr precursor produced inExample 2;

FIG. 7 is a TGA graph illustrating the percentage of weight loss ofTiBr₄:SEtPr upon temperature increase;

FIG. 8 is a flow chart showing the process of Example 3;

FIG. 9 is a schematic side view of the NH₂ terminated substrate producedby Step 1 of FIG. 8;

FIG. 10 is a schematic side view of the substrate at the start of Step 2of FIG. 8;

FIG. 11 is a schematic side view of the reactions with the substrate andthe reaction by-products produced by Step 2 of FIG. 8;

FIG. 12 is schematic side view of the substrate produced by Step 3 ofFIG. 8;

FIG. 13 is a schematic side view of the substrate during Step 4 of FIG.8; and

FIG. 14 is a graph showing the titanium nitride film growth rate andresulting titanium nitride film thickness per number of ALD cycles usingthe TiBr₄:S(nPr)₂ precursor.

DESCRIPTION OF PREFERRED EMBODIMENTS

Ti-containing film forming compositions are disclosed. The Ti-containingfilm forming compositions comprise Ti halide-containing precursorshaving one of the following formula:

TiX_(b):Ac

Ti(NR₂)_(y)(X)_(z)

Ti(—N—R″—N—)_(y)(X)_(z)

with b=3 when c=3; b=4 when c=1 or 2; y=1-3; z=1-3; y+z=4; X=Br or I;A=SR₂, SeR₂, TeR₂, or PR₃; each R is independently H, a C1-C5hydrocarbon, or SiR′₃, with each R′ independently being H or a C1-C5hydrocarbon; and R″=C1-C5 hydrocarbon. Preferably, b=4 and c=1 or 2.However, in certain embodiments, the octahedral TiX₃:A₃ is the moststable embodiment.

Exemplary Ti halide-containing precursors having the formula TiX₄:Ac,with c=1 or 2 and X=Br or I; include TiX₄:SR₂, TiX₄:(SR₂)₂, TiX₄:SeR₂,TiX₄:(SeR₂)₂. TiX₄:TeR₂, or TiX₄:(TeR₂)₂, with each R independently aC1-C5 hydrocarbon. The Ti halide-containing precursor may be liquid whendifferent Rs are used (e.g., SEtPr). The different R groups may decreaseintermolecular forces, resulting in lower melting points and viscositiesthan molecules that have the same R groups (i.e., SEtPr may have a lowermelting point and viscosity than SEt₂ and/or SPr₂). The two R groups mayalso be linked to form a cyclic structure. When c=2, each R ispreferably a smaller hydrocarbon ligand due to steric hindrance. Forexample, when c=2, each R may independently be a C1-2 hydrocarbon. Incontrast, when c=1, the precursor enjoys less steric hindrance and eachR may independently be a C3-C5 hydrocarbon.

When X=Br and A=SR₂, exemplary TiX₄:Ac precursors include TiBr₄:SEtPr,TiBr₄:SPr₂, TiBr₄:S(nPr)₂, TiBr₄:S(iPr)₂, TiBr₄:SBu₂, TiBr₄:S(nBu)₂,TiBr₄:S(tBu)₂, TiBr₄:S(iBu)₂, TiBr₄:S(sBu)₂, TiBr₄:(SMe₂)₂,TiBr₄:(SEt₂)₂, TiBr₄:(SMeEt)₂, or TiBr₄:(tetrahydrothiophene)₂.

When X=I and A=SR₂, exemplary TiX₄:Ac precursors include TiI₄:SEtPr,TiI₄:S(nPr)₂, TiI₄:S(iPr)₂, TiI₄:SBu₂, TiI₄:S(nBu)₂, TiI₄:S(tBu)₂,TiI₄:S(iBu)₂, TiI₄:S(sBu)₂, TiI₄:(SEt₂)₂, TiI₄:(SMe₂)₂, TiI₄:(SMeEt)₂,or TiI₄:(tetrahydrothiophene)₂.

Exemplary TiX₄:(SeR₂)_(c) precursors include TiBr₄:SeMePr, TiBr₄:SePr₂,TiBr₄:SeBu₂, TiBr₄:(SeMe₂)₂, TiBr₄:(SeEt₂)₂, TiBr₄:(SeMeEt)₂, orTiBr₄:(tetrahydroselenophene)₂.

Exemplary TiX₄:(TeR₂)_(c) precursors include TiBr₄:TeMePr, TiBr₄:TePr₂,TiBr₄:TeBu₂, TiBr₄:(TeMe₂)₂, TiBr₄:(TeEt₂)₂, TiBr₄:(TeMeEt)₂, orTiBr₄:(tetrahydrotellurophene)₂.

These precursors may be prepared by direct reaction of the Ti halidewith an excess of the ligand in any solvent. See, e.g., Fowles et al.,Journal of the less common metals, 8, 1965, pp. 47-50. The halidestarting material is commercially available. The SR₂, SeR₂, and TeR₂starting material may be commercially available and/or synthesized bymethods known in the literature. An exemplary synthesis methodcontaining further details is provided in the Examples that follow.

Exemplary Ti halide-containing precursors having the formula TiX_(b):Ac,with b=3 or 4, c=1-3, and X=Br or I; include TiX_(b):(PR₃)_(c) with eachR independently H or a C1-C5 hydrocarbon. A may be PRR′R″, with R notequal to R′ and R″. Adjacent R groups may also be linked to form acyclic structure. When c=2, each R is preferably a smaller hydrocarbonligand due to steric hindrance. For example, when c=2, each R mayindependently be H or a C1-2 hydrocarbon. In contrast, when c=1, theprecursor enjoys less steric hindrance and each R may independently be aC3-C10 hydrocarbon. Exemplary TiX_(b):(PR₃)_(c) precursors includeTiBr₄:PH₃, TiBr₄:(PH₃)₂, or TiBr₃:(PH₃)₃. These precursors may beprepared by direct reaction of the Ti halide with an excess of the PR₃.See, e.g., R. Holtje, Zeitschrift fuer Anorganische und AllgemeineChemie, 1930, 190, pp 241-256.

Another exemplary Ti halide-containing precursor has the formulaTiX₄:(R₂P—(CH₂)_(n)—PR₂) or TiX₃:(R₂P—(CH₂)_(n)—PR₂), with each Rindependently a C1-5 hydrocarbon and n=1-4. These precursors may besynthesized by direct reaction of the Ti halide with an excess of theR₂P—CH₂—PR₂. See, e.g., Fowles et al., Journal of the less commonmetals, 8, 1965, pp. 47-50. One of ordinary skill in the art willrecognize that the R₂P—CH₂—PR₂ ligand may reduce Ti(IV) to Ti(III). As aresult, the Ti-containing film forming compositions may include acombination of both of the TiX₄:(R₂P—(CH₂)_(n)—PR₂) andTiX₃:(R₂P—(CH₂)_(n)—PR₂) precursors.

When X=Br, exemplary TiX₄:(R₂P—(CH₂)_(n)—PR₂) precursors includeTiBr₄:(Me₂P—(CH₂)_(n)—PMe₂), TiBr₄:(EtMeP—(CH₂)_(n)—PMeEt),TiBr₄:(Et₂P—(CH₂)_(n)-PEt₂), TiBr₄:(iPr₂P—(CH₂)_(n)-PiPr₂),TiBr₄:(HiPrP-(CH₂)_(n)-PHiPr), TiBr₄:(tBu₂P—(CH₂)_(n)-PtBu₂),TiBr₄:(tBuHP-(CH₂)_(n)-PHtBu), TiBr₄:(tAmHP-(CH₂)_(n)-PHtAm),TiBr₄:(Me₂P—(CH₂)—PMe₂), TiBr₄:(EtMeP—(CH₂)—PMeEt),TiBr₄:(Et₂P—(CH₂)-PEt₂), TiBr₄:(iPr₂P—(CH₂)—PiPr₂),TiBr₄:(HiPrP-(CH₂)-PHiPr), TiBr₄:(tBu₂P—(CH₂)-PtBu₂),TiBr₄:(tBuHP-(CH₂)—PHtBu), TiBr₄:(tAmHP-(CH₂)-PHtAm),TiBr₄:(Me₂P—(CH₂)₂—PMe₂), TiBr₄:(EtMeP—(CH₂)₂—PMeEt),TiBr₄:(Et₂P—(CH₂)₂-PEt₂), TiBr₄:(iPr₂P—(CH₂)₂-PiPr₂),TiBr₄:(HiPrP-(CH₂)₂-PHiPr), TiBr₄:(tBu₂P—(CH₂)₂-PtBu₂),TiBr₄:(tBuHP-(CH₂)₂-PHtBu), or TiBr₄:(tAmHP-(CH₂)₂-PHtAm).

Exemplary TiX₃:(R₂P—(CH₂)_(n)—PR₂) precursors includeTiBr₃:(Me₂P—(CH₂)_(n)—PMe₂), TiBr₃:(EtMeP—(CH₂)_(n)—PMeEt),TiBr₃:(Et₂P—(CH₂)_(n)-PEt₂), TiBr₃:(iPr₂P—(CH₂)_(n)-PiPr₂),TiBr₃:(HiPrP-(CH₂)_(n)-PHiPr), TiBr₃:(tBu₂P—(CH₂)_(n)-PtBu₂),TiBr₃:(tBuHP-(CH₂)_(n)-PHtBu), TiBr₃:(tAmHP-(CH₂)_(n)-PHtAm),TiBr₃:(Me₂P—(CH₂)—PMe₂), TiBr₃:(EtMeP—(CH₂)—PMeEt),TiBrs:(Et₂P—(CH₂)-PEt₂), TiBr₃:(iPr₂P—(CH₂)-PiPr₂),TiBr₃:(HiPrP-(CH₂)-PHiPr), TiBr₃:(tBu₂P—(CH₂)-PtBu₂),TiBr₃:(tBuHP-(CH₂)-PHtBu), TiBr₃:(tAmHP-(CH₂)-PHtAm),TiBr₃:(Me₂P—(CH₂)₂—PMe₂), TiBr₃:(EtMeP—(CH₂)₂—PMeEt),TiBr₃:(Et₂P—(CH₂)₂-PEt₂), TiBr₃:(iPr₂P—(CH₂)₂-PiPr₂),TiBr₃:(HiPrP-(CH₂)₂-PHiPr), TiBr₃:(tBu₂P—(CH₂)₂-PtBu₂),TiBr₃:(tBuHP-(CH₂)₂-PHtBu), or TiBr₃:(tAmHP-(CH₂)₂-PHtAm).

When X=I, exemplary TiX₄:(R₂P—(CH₂)_(n)—PR₂) precursors includeTiI₄:(Me₂P—(CH₂)_(n)—PMe₂), TiI₄:(EtMeP—(CH₂)_(n)—PMeEt),TiI₄:(Et₂P—(CH₂)_(n)-PEt₂), TiI₄:(iPr₂P—(CH₂)_(n)-PiPr₂),TiI₄:(HiPrP-(CH₂)_(n)-PHiPr), TiI₄:(tBu₂P—(CH₂)_(n)-PtBu₂),TiI₄:(tBuHP-(CH₂)_(n)-PHtBu), TiI₄:(tAmHP-(CH₂)_(n)-PHtAm),TiI₄:(Me₂P—(CH₂)—PMe₂), TiI₄:(EtMeP—(CH₂)—PMeEt),TiI₄:(Et₂P—(CH₂)-PEt₂), TiI₄:(iPr₂P—(CH₂)-PiPr₂),TiI₄:(HiPrP-(CH₂)-PHiPr), TiI₄:(tBu₂P—(CH₂)-PtBu₂),TiI₄:(tBuHP-(CH₂)-PHtBu), TiI₄:(tAmHP-(CH₂)-PHtAm),TiI₄:(Me₂P—(CH₂)₂—PMe₂), TiI₄:(EtMeP—(CH₂)₂—PMeEt),TiI₄:(Et₂P—(CH₂)₂-PEt₂), TiI₄:(iPr₂P—(CH₂)₂-PiPr₂),TiI₄:(HiPrP-(CH₂)₂-PHiPr), TiI₄:(tBu₂P—(CH₂)₂—PtBU₂),TiI₄:(tBuHP-(CH₂)₂-PHtBu), or TiI₄:(tAmHP-(CH₂)₂-PHtAm).

Exemplary TiX₃:(R₂P—(CH₂)_(n)—PR₂) precursors includeTiI₃:(Me₂P—(CH₂)_(n)—PMe₂), TiI₃:(EtMeP—(CH₂)_(n)—PMeEt),TiI₃:(Et₂P—(CH₂)_(n)-PEt₂), TiI₃:(iPr₂P—(CH₂)_(n)-PiPr₂),TiI₃:(HiPrP-(CH₂)_(n)-PHiPr), TiI₃:(tBu₂P—(CH₂)_(n)-PtBu₂),TiI₃:(tBuHP-(CH₂)_(n)-PHtBu), TiI₃:(tAmHP-(CH₂)_(n)-PHtAm),TiI₃:(Me₂P—(CH₂)—PMe₂), TiI₃:(EtMeP—(CH₂)—PMeEt),TiI₃:(Et₂P—(CH₂)-PEt₂), TiI₃:(iPr₂P—(CH₂)-PiPr₂),TiI₃:(HiPrP-(CH₂)-PHiPr), TiI₃:(tBU₂P—(CH₂)-PtBu₂),TiI₃:(tBuHP-(CH₂)-PHtBu), TiI₃:(tAmHP-(CH₂)-PHtAm),TiI₃:(Me₂P—(CH₂)₂—PMe₂), TiI₃:(EtMeP—(CH₂)₂—PMeEt),TiI₃:(Et₂P—(CH₂)₂-PEt₂), TiI₃:(iPr₂P—(CH₂)₂-PiPr₂),TiI₃:(HiPrP-(CH₂)₂-PHiPr), TiI₃:(tBu₂P—(CH₂)₂-PtBu₂),TiI:(tBuHP-(CH₂)₂-PHtBu), or TiI₃:(tAmHP-(CH₂)₂-PHtAm).

Exemplary Ti halide-containing precursors having the formula TiX₄:Ac,with c=1 and X=Br or I; include TiX₄:(R(═O)Cl), with R being a C2-C6hydrocarbon. Exemplary TiX₄:(R(═O)Cl) precursors includeTiBr₄:(Me-C(═O)Cl), TiBr₄:(Ph-C(═O)Cl), or TiI₄:(Me-C(═O)Cl). Theseprecursors may be prepared by direct reaction of the Ti halide with anexcess of the ligand without solvent or in CCl₄, benzene, toluene. Seee.g. Emeléus et al., Complexes of Titanium and Zirconium Halides withOrganic Ligands, J. Chemical Society (Resumed), 1958, pp. 4245-50.

Exemplary Ti halide-containing precursors having the formula TiX₄:Ac,with c=1 and X=Br or I; include TiX₄:(RNO₂), with R being a C1-C10hydrocarbon. Exemplary TiX₄:(RNO₂) precursors include TiBr₄:(MeNO₂),TiI₄:(MeNO₂), TiBr₄:(EtNO₂), TiBr₄:(PrNO₂), or TiBr₄:(PhNO₂). Theseprecursors may be prepared by direct reaction of the Ti halide with anexcess of the ligand without solvent or in CCl₄, benzene, toluene. Seee.g. Emeléus et al., Complexes of Titanium and Zirconium Halides withOrganic Ligands, J. Chemical Society (Resumed), 1958, pp. 4245-50.

Exemplary Ti halide-containing precursors having the formula TiX₄:Ac,with c=2 and X=Br or I; include TiX₄:(R═N)₂, with R being a C2-C10hydrocarbon. Exemplary TiX₄:(R═N)_(c) precursors includeTiBr₄:(Me-C≡N)₂, TiBr₄:(Et-C≡N)₂, TiBr₄:(Pr—C≡N)₂, TiBr₄:(Bu-C≡N)₂, orTiBr₄:(Ph-C≡N)₂. These precursors may be prepared by direct reaction ofthe Ti halide with an excess of the ligand without solvent or in CCl₄,benzene, toluene. See e.g. Emeléus et al., Complexes of Titanium andZirconium Halides with Organic Ligands, J. Chemical Society (Resumed),1958, pp. 4245-50.

Exemplary Ti halide-containing precursors having the formula TiX₄:Ac,with c=1 or 2 and X=Br or I; include TiX₄:(pyridine)_(c). ExemplaryTiX₄:(pyridine)_(c) precursors include TiBr₄:pyridine. These precursorsmay be prepared by direct reaction of the Ti halide with an excess ofthe ligand without solvent or in CCl₄, benzene, toluene. See e.g.Emeléus et al., Complexes of Titanium and Zirconium Halides with OrganicLigands, J. Chemical Society (Resumed), 1958, pp. 4245-50.

Exemplary Ti halide-containing precursors having the formula TiX₄:Ac,with c=1 or 2 and X=Br or I; include TiX₄:(piperidine)_(c). ExemplaryTiX₄:(piperidine)_(c) precursors include TiBr₄:piperidine orTiBr₄:2,2,6,6-tetramethylpiperidine. These precursors may be synthesizedby direct reaction of the Ti halide with an excess of the ligand inbenzene or toluene. See e.g. Dermer et al. in Zeitschrift fuerAnorganishce und Allgemeine Chemie (1934) 221 pp. 83-96.

Exemplary Ti halide-containing precursors having the formulaTi(NR₂)_(y)(X)_(z), with y=1-3, z=1-3, y+z=4, X=Br or I, and each Rindependently H, a C1-C10 hydrocarbon, or SiR′₃, with each R′independently being H or a C1-C10 hydrocarbon include TiX₃(NR₂),TiX₂(NR₂)₂, or TiX(NR₂)₃. The two R groups may be linked to form acyclic structure.

Exemplary TiX₃(NR₂) precursors include TiBr₃(NR₂) and TiI₃(NR₂), such asTiBr₃(NEt₂), TiBr₃(pyrrolidine), TiBr₃(pyridine), or TiBr₃(piperidine).These precursors may be synthesized by reaction of TiX₄ with Me₃Si(NR₂)as described by Buerger et al., Zeitschrift fuer Anorganische undAllgemeine CHemie, 370 (5-6), 1969, pp. 275-282.

Exemplary TiX₂(NR₂)₂ precursors include TiBr₂(NR₂)₂ and TiI₂(NR₂)₂, suchas TiBr₂(NMe₂)₂. These precursors may be synthesized by metathesis ofTiX₄ with Ti(NR₂)₄ as described by Buerger et al., Zeitschrift fuerAnorganische und Allgemeine CHemie, 370 (5-6), 1969, pp. 275-282.

Exemplary TiX(NR₂)₃ precursors include TiBr(NR₂)₃ and TiI(NR₂)₃. Theseprecursors may be synthesized by reaction of TiX₄ with Ti(NR₂)₄ asdescribed by Buerger et al., Zeitschrift fuer Anorganische undAllgemeine CHemie, 370 (5-6), 1969, pp. 275-282.

Exemplary Ti halide-containing precursors having the formulaTi(—N—R″—N—)_(y)(X)_(z), with y=1-3, z=1-3, y+z=4, X=Br or I, and R″ aC1-C10 hydrocarbon, include TiBr₃(N^(iPr)-fmd), TiBr₃(N^(iPr) Me-amd),or TiBr₂(—N(R)—C₂H₄—N(R)—)₂. These precursors may be synthesized byreaction of TiBr₄ or TiI₄ and trimethylsilyl derivative of amidinateligand (e.g. TiBr₄ and TMS-N^(Pr) Me-amd). Exemplary synthesis methodsare described for titanium chloride complexes in D. Fenske et al. Z.Naturforsch. 43b, 1611-1615 (1988); D. Liguori et al., Macromolecules2003, 36, 5451-5458.

One of ordinary skill in the art will recognize the sources for theequipment used to practice the disclosed synthesis methods. Some levelof customization of the components may be required based upon thedesired temperature range, pressure range, local regulations, etc.Exemplary equipment suppliers include Buchi Glass Uster AG, ShandongChemSta Machinery Manufacturing Co. Ltd., Jiangsu Shajiabang ChemicalEquipment Co. Ltd, etc.

To ensure process reliability, the Ti-containing film formingcompositions may be purified by continuous or fractional batchdistillation or sublimation prior to use to a purity ranging fromapproximately 93% w/w to approximately 100% w/w, preferably ranging fromapproximately 99% w/w to approximately 100% w/w. The Ti-containing filmforming compositions may contain any of the following impurities:undesired congeneric species; excess adduct; hydrogen halides (HX);solvents; halogenated metal compounds (TiX); or other reaction products.In one alternative, the total quantity of these impurities is below 0.1%w/w.

High purity product may be obtained by using high purity reactants. Forexample, the SR₂ adduct may contain traces of SR′2, wherein R≠R′.Preferably, the Ti-containing film forming composition comprises betweenapproximately 0% w/w and 0.2% w/w of TiX_(b):(SR′₂)_(c), wherein R′≠R.The SR′₂ levels may be analyzed in either the starting material orfinished product using GC and/or NMR.

The Ti-containing film forming compositions should contain no waterbecause the molecules will hydrolyze (e.g., between approximately 0% w/wand 5 ppm of H₂O). Any water present in the Ti-containing film formingcompositions may result in formation of undesired oxyhalides(TiBr₂(═O)or TiI₂(═O)), hydroxyhalides (TiBr₃(OH) or TiI₃(OH)), and oxides (TiO₂).The total amount of the combination of these three impurities in theTi-containing film forming composition should be less than 0.2% w/w, andpreferably less than 0.1% w/w. These impurities may be detected usingNMR, FTIR, TGA, or combinations thereof.

The amount of hydrogen halide (i.e., HBr or HI) reaction by-productshould also be minimized because it may react with components in thedelivery lines and deposition chamber. HX may also be detrimental to theunderlying substrate. The Ti-containing film forming compositions shouldcontain less than 0.1% w/w and preferably less than 0.01% w/w of any HXby-products. These impurities may be detected using FTIR and/or GC.

The concentration of each of hexane, pentane, dimethyl ether, or anisolein the purified Ti-containing film forming compositions may range fromapproximately 0% w/w to approximately 5% w/w, preferably fromapproximately 0% w/w to approximately 0.1% w/w. Solvents may be used inthe composition's synthesis. Separation of the solvents from theprecursor may be difficult if both have similar boiling points. Coolingthe mixture may produce solid precursor in liquid solvent, which may beseparated by filtration. Vacuum distillation may also be used, providedthe precursor reaction product is not heated above approximately itsdecomposition point.

In one alternative, the disclosed Ti-containing film formingcompositions contain less than 5% v/v, preferably less than 1% v/v, morepreferably less than 0.1% v/v, and even more preferably less than 0.01%v/v of any of its undesired congeneric species, reactants, or otherreaction products. This alternative may provide better processrepeatability. This alternative may be produced by distillation of theTi-containing precursors.

In another alternative, the disclosed Ti-containing film formingcompositions may contain between 5% v/v and 50% v/v of one or morecogeneric Ti halide-containing precursors, reactants, or other reactionproducts, particularly when the mixture provides improved processparameters or isolation of the target compound is too difficult orexpensive. For example, a mixture of two Ti halide-containingprecursors, such as TiBr₄:(iPr₂P—(CH₂)-PiPr₂) andTiBrs:(iPr₂P—(CH₂)-PiPr₂), may produce a stable, liquid mixture suitablefor vapor deposition.

The concentration of trace metals and metalloids in the purifiedTi-containing film forming compositions may each range fromapproximately 0 ppm to approximately 5 ppm, preferably fromapproximately 0 ppm to approximately 1 ppm, and more preferably fromapproximately 0 ppb to approximately 500 ppb. These metal impuritiesinclude, but are not limited to, Aluminum (Al), Silver (Ag), Arsenic(As), Barium (Ba), Beryllium (Be), Bismuth (Bi), Cadmium (Cd), Calcium(Ca), Chromium (Cr), Cobalt (Co), Copper (Cu), Gallium (Ga), Germanium(Ge), Hafnium (Hf), Indium (In), Iron (Fe), Lead (Pb), Lithium (Li),Magnesium (Mg), Manganese (Mn), Tungsten (W), Nickel (Ni), Potassium(K), Sodium (Na), Strontium (Sr), Thorium (Th), Tin (Sn), Uranium (U),Vanadium (V), Zinc (Zn), and Zirconium (Zr).

The benefit of the disclosed precursors is a reduced melting point whencompared to their TiX₄ analogs. For titanium iodide-containingprecursors, the Ti halide-containing precursor may have a melting pointbetween approximately −50° C. and approximately 150° C. at standardtemperature and pressure, preferably between approximately −50° C. andapproximately 30° C. at standard temperature pressure. For titaniumbromide-containing precursors, the Ti halide-containing precursor mayhave a melting point between approximately −50° C. and approximately 39°C. at standard temperature and pressure. Preferably, the Tihalide-containing precursor is a liquid at standard temperature andpressure because the reproducible and stable production of vapor fromsolid precursors is challenging at best. Solid precursors may bedissolved in a solvent and the solution vaporized, but that mayintroduce impermissible contamination issues from the solvent into theresulting film. Alternatively, a sublimator may be used to producevapors from solid materials directly, but the grain size, soliddistribution in the sublimator, and vapor pressure of the solid itselfmake it very difficult to provide a consistent and reproducibleconcentration of the vapor to the semiconductor process.

Applicants also expect that the Ti-adduct bonds will break at thedeposition temperature. As a result, no film contamination is expectedfrom inclusion of the adduct in the Ti halide-containing precursor. Assuch, these precursors should behave as TiBr₄ and TiI₄, but be easier tohandle and use owing to their lower melting point. The disclosed Tihalide-containing precursor are also better than TiCl₄ due to a lowerdeposition temperature and the absence of highly corrosive Cl.

Finally, Applicants believe that the disclosed Ti-containing filmforming compositions may be more stable and less hydrolysable than theanalogous chloride containing compositions. The disclosed Ti-containingfilm forming compositions may also exhibit less etching damage to thesubstrate and reactor than the analogous chloride containingcompositions. Testing was performed using the TiBr₄—S(nPr)₂ moleculesand no substrate damage was evident on A₂O₃, HfO₂, Nb₂O₅, SiO₂, or ZrO₂films at 300° C., 350° C., 400° C., or 450° C. This is somewhatsurprising because HBr is more acidic than HCl (pKa HCl=−7, pKa HBr=−9,and pKa HI=−10).

The Ti-containing film forming compositions may exhibit (i) sufficientvolatility to provide a rapid and reproducible delivery into thereaction chamber from the vessel in which they are stored, (ii) highthermal stability to avoid decomposition during the storage in thecanister and to enable self-limiting growth in ALD mode at hightemperature, typically >150° C. for dielectric films and >275° C. forconductive films, (iii) appropriate reactivity toward the substrateterminal functions and with the reacting gas to an easy conversion intothe desired film, and (iv) high purity to obtain a film with lowimpurities.

Also disclosed are methods for forming Ti-containing layers on asubstrate using a vapor deposition process. The method may be useful inthe manufacture of semiconductor, photovoltaic, LCD-TFT, or flat paneltype devices. The disclosed Ti-containing film forming compositions maybe used to deposit thin Ti-containing films using any deposition methodsknown to those of skill in the art. Examples of suitable vapordeposition methods include chemical vapor deposition (CVD) or atomiclayer deposition (ALD). Exemplary CVD methods include thermal CVD,plasma enhanced CVD (PECVD), pulsed CVD (PCVD), low pressure CVD(LPCVD), sub-atmospheric CVD (SACVD) or atmospheric pressure CVD(APCVD), hot-wire CVD (HWCVD, also known as cat-CVD, in which a hot wireserves as an energy source for the deposition process), radicalsincorporated CVD, and combinations thereof. Exemplary ALD methodsinclude thermal ALD, plasma enhanced ALD (PEALD), spatial isolation ALD,hot-wire ALD (HWALD), radicals incorporated ALD, and combinationsthereof. Super critical fluid deposition may also be used. Thedeposition method is preferably ALD, spatial ALD, or PE-ALD to providesuitable step coverage and film thickness control. The disclosedTi-containing film forming compositions are particularly suitable forALD processes because their thermal stability enables perfectself-limited growth.

The disclosed Ti-containing film forming composition may be suppliedeither neat or may further comprise a suitable solvent, such as C1-C16hydrocarbons, C1-C16 halogenated hydrocarbons, ketones, ethers, glymes,esters, tetrahydrofurans, dimethyl oxalate (DMO), and combinationsthereof. The C1-C16 hydrocarbons and the C1-C16 halogenated hydrocarbonsmay be saturated or unsaturated. Exemplary solvents include but are notlimited to tetrahydrofuran, DMO, ethyl benzene, xylene, mesitylene,decane, and/or dodecane. The adduct may also be used as a solvent whenthe Ti-containing film forming composition is introduced into thereactor via direct liquid injection. One of ordinary skill in the artwill recognize that the adduct is not a suitable solvent for bubblersbecause it will evaporate prior to vaporization of the Tihalide-containing precursor (i.e., there will be no vapor of the Tihalide-containing precursor in the vapor of the adduct solvent whenintroduced into the reactor via bubbler due to the differences in vaporpressure between the two). The disclosed Ti halide-containing precursorsmay be present in varying concentrations in the solvent. The differencebetween the boiling point of the Ti-halide containing precursor and thatof the solvent should range from approximately 0° C. to approximately80° C.

While the precursors are ideally liquids and vaporized in bubblers ordirect liquid injection systems, the use of solid precursors for ALD andCVD precursor vaporization is also possible using sublimators such asones disclosed in PCT Publication WO2009/087609 to Xu et al.Alternatively, solid precursors may be mixed or dissolved in a solventto reach a usable melting point and viscosity for usage by Direct LiquidInjection systems.

The neat or blended Ti-containing film forming compositions areintroduced into a reactor in vapor form by conventional means, such astubing and/or flow meters. The vapor form may be produced by vaporizingthe neat or blended composition through a conventional vaporization stepsuch as direct vaporization, distillation, or by bubbling, or by using asublimator such as the one disclosed in PCT Publication WO2009/087609 toXu et al. The composition may be fed in a liquid state to a vaporizerwhere it is vaporized before it is introduced into the reactor.Alternatively, the composition may be vaporized by passing a carrier gasinto a container containing the compound or by bubbling the carrier gasinto the compound. The carrier gas may include, but is not limited to,Ar, He, N₂, and mixtures thereof. Bubbling with a carrier gas may alsoremove any dissolved oxygen present in the neat or blended compoundsolution. The carrier gas and vapor form of the composition are thenintroduced into the reactor as a vapor.

If necessary, the container may be heated to a temperature that permitsthe composition to be in its liquid phase and to have a sufficient vaporpressure. The container may be maintained at temperatures in the rangeof, for example, approximately 50° C. to approximately 180° C. Thoseskilled in the art recognize that the temperature of the container maybe adjusted in a known manner to control the amount of compositionvaporized. Preferably, the container is maintained at a temperature thatresults in the Ti-containing film forming composition having a viscosityranging from approximately 1 to approximately 50 cps, preferably betweenapproximately 1 to approximately 20 cps. Such viscosities make theTi-containing film forming compositions suitable for introduction intothe reactor using direct liquid injection.

The Ti-containing film forming compositions may be delivered to asemiconductor processing tool by the disclosed Ti-containing filmforming composition delivery devices. FIGS. 1 and 2 show two embodimentsof the disclosed delivery devices 1.

FIG. 1 is a side view of one embodiment of the Ti-containing filmforming composition delivery device 1. In FIG. 1, the disclosedTi-containing film forming composition 11 is contained within acontainer 2 having at least two conduits, an inlet conduit 3 and anoutlet conduit 4. One of ordinary skill in the precursor art willrecognize that the container 2, inlet conduit 3, and outlet conduit 4are manufactured to prevent the escape of the gaseous form of theTi-containing film forming composition 11, even at elevated temperatureand pressure.

Suitable valves include spring-loaded or tied diaphragm valves. Thevalve may further comprise a restrictive flow orifice (RFO). Thedelivery device 1 should be connected to a gas manifold and in anenclosure. The gas manifold should permit the safe evacuation andpurging of the piping that may be exposed to air when the deliverydevice 1 is replaced so that any residual amount of the material doesnot react.

The delivery device 1 must be leak tight and be equipped with valvesthat do not permit escape of even minute amounts of the material whenclosed. The delivery device 1 fluidly connects to other components ofthe semiconductor processing tool, such as the gas cabinet disclosedabove, via valves 6 and 7. Preferably, the container 2, inlet conduit 3,valve 6, outlet conduit 4, and valve 7 are typically made of 316L EPstainless steel.

In FIG. 1, the end 8 of inlet conduit 3 is located above the surface ofthe Ti-containing film forming composition 11, whereas the end 9 of theoutlet conduit 4 is located below the surface of the Ti-containing filmforming composition 11. In this embodiment, the Ti-containing filmforming composition 11 is preferably in liquid form. An inert gas,including but not limited to nitrogen, argon, helium, and mixturesthereof, may be introduced into the inlet conduit 3. The inert gaspressurizes the container 2 so that the liquid Ti-containing filmforming composition 11 is forced through the outlet conduit 4 and tocomponents in the semiconductor processing tool (not shown). Thesemiconductor processing tool may include a vaporizer which transformsthe liquid Ti-containing film forming composition 11 into a vapor, withor without the use of a carrier gas such as helium, argon, nitrogen ormixtures thereof, in order to deliver the vapor to a chamber where awafer to be repaired is located and treatment occurs in the vapor phase.Alternatively, the liquid Ti-containing film forming composition 11 maybe delivered directly to the wafer surface as a jet or aerosol.

FIG. 2 is a side view of a second embodiment of the Ti-containing filmforming composition delivery device 1. In FIG. 2, the end 8 of inletconduit 3 is located below the surface of the Ti-containing film formingcomposition 11, whereas the end 9 of the outlet conduit 4 is locatedabove the surface of the Ti-containing film forming composition 11. FIG.2 also includes an optional heating element 14, which may increase thetemperature of the Ti-containing film forming composition 11. TheTi-containing film forming composition 11 may be in solid or liquidform. An inert gas, including but not limited to nitrogen, argon,helium, and mixtures thereof, is introduced into the inlet conduit 3.The inert gas flows through the Ti-containing film forming composition11 and carries a mixture of the inert gas and vaporized Ti-containingfilm forming composition 11 to the outlet conduit 4 and to thecomponents in the semiconductor processing tool.

Both FIGS. 1 and 2 include valves 6 and 7. One of ordinary skill in theart will recognize that valves 6 and 7 may be placed in an open orclosed position to allow flow through conduits 3 and 4, respectively. Inanother alternative, the inlet conduit 3 and outlet conduit 4 may bothbe located above the surface of the Ti-containing film formingcomposition 11 without departing from the disclosure herein.Furthermore, inlet conduit 3 may be a filling port.

In another alternative, either delivery device 1 in FIG. 1 or 2, or asimpler delivery device having a single conduit terminating above thesurface of any solid or liquid present, may be used if the Ti-containingfilm forming composition 11 is in vapor form or if sufficient vaporpressure is present above the solid/liquid phase. In this case, theTi-containing film forming composition 11 is delivered in vapor formthrough the conduit 3 or 4 simply by opening the valve 6 in FIG. 1 or 7in FIG. 2, respectively. The delivery device 1 may be maintained at asuitable temperature to provide sufficient vapor pressure for theTi-containing film forming composition 11 to be delivered in vapor form,for example by the use of an optional heating element 14.

When the Ti-containing film forming compositions are solids, theirvapors may be delivered to the reactor using a sublimator. FIG. 3 showsone embodiment of a suitable sublimator 100. The sublimator 100comprises a container 33. Container 33 may be a cylindrical container,or alternatively, may be any shape, without limitation. The container 33is constructed of materials such as stainless steel, nickel and itsalloys, quartz, glass, and other chemically compatible materials,without limitation. In certain instances, the container 33 isconstructed of another metal or metal alloy, without limitation. Incertain instances, the container 33 has an internal diameter from about8 centimeters to about 55 centimeters and, alternatively, an internaldiameter from about 8 centimeters to about 30 centimeters. As understoodby one skilled in the art, alternate configurations may have differentdimensions.

Container 33 comprises a sealable top 15, sealing member 18, and gasket20. Sealable top 15 is configured to seal container 33 from the outerenvironment. Sealable top 15 is configured to allow access to thecontainer 33. Additionally, sealable top 15 is configured for passage ofconduits into container 33. Alternatively, sealable top 15 is configuredto permit fluid flow into container 33. Sealable top 15 is configured toreceive and pass through a conduit comprising a dip tube 92 to remain influid contact with container 33. Dip tube 92 having a control valve 90and a fitting 95 is configured for flowing carrier gas into container33. In certain instances, dip tube 92 extends down the center axis ofcontainer 33. Further, sealable top 15 is configured to receive and passthrough a conduit comprising outlet tube 12. The carrier gas and vaporof the Ti-containing film forming composition is removed from container33 through the outlet tube 12. Outlet tube 12 comprises a control valve10 and fitting 5. In certain instances, outlet tube 12 is fluidlycoupled to a gas delivery manifold, for conducting carrier gas from thesublimator 100 to a film deposition chamber.

Container 33 and sealable top 15 are sealed by at least two sealingmembers 18; alternatively, by at least about four sealing members. Incertain instance, sealable top 15 is sealed to container 33 by at leastabout eight sealing members 18. As understood by one skilled in the art,sealing member 18 releasably couples sealable top 15 to container 33,and forms a gas resistant seal with gasket 20. Sealing member 18 maycomprise any suitable means known to one skilled in the art for sealingcontainer 33. In certain instances, sealing member 18 comprises athumbscrew.

As illustrated in FIG. 3, container 33 further comprises at least onedisk disposed therein. The disk comprises a shelf, or horizontalsupport, for solid material. In certain embodiments, an interior disk 30is disposed annularly within the container 33, such that the disk 30includes an outer diameter or circumference that is less than the innerdiameter or circumference of the container 33, forming an opening 31. Anexterior disk 86 is disposed circumferentially within the container 33,such that the disk 86 comprises an outer diameter or circumference thatis the same, about the same, or generally coincides with the innerdiameter of the container 33. Exterior disk 86 forms an opening 87disposed at the center of the disk. A plurality of disks is disposedwithin container 33. The disks are stacked in an alternating fashion,wherein interior disks 30, 34, 36, 44 are vertically stacked within thecontainer with alternating exterior disks 62, 78, 82, 86. Inembodiments, interior disks 30, 34, 36, 44 extend annularly outward, andexterior disks 62, 78, 82, 86 extend annularly toward the center ofcontainer 33. As illustrated in the embodiment of FIG. 3, interior disks30, 34, 36, 44 are not in physical contact with exterior disks 62, 78,82, 86.

The assembled sublimator 100 comprises interior disks 30, 34, 36, 44comprising aligned and coupled support legs 50, interior passage 51,concentric walls 40, 41, 42, and concentric slots 47, 48, 49. Theinterior disks 30, 34, 36, 44 are vertically stacked, and annularlyoriented about the dip tube 92. Additionally, the sublimator comprisesexterior disks 62, 78, 82, 86. As illustrated in FIG. 3, the exteriordisks 62, 78, 82, 86 should be tightly fit into the container 33 for agood contact for conducting heat from the container 33 to the disks 62,78, 82, 86. Preferably, the exterior disks 62, 78, 82, 86 are coupledto, or in physical contact with, the inner wall of the container 33.

As illustrated, exterior disks 62, 78, 82, 86 and interior disks 30, 34,36, 44 are stacked inside the container 33. When assembled in container33 to form sublimator 100, the interior disks 30, 34, 36, 44 form outergas passages 31, 35, 37, 45 between the assembled exterior disks 62, 78,82, 86. Further, exterior disks 62, 78, 82, 86 form inner gas passages56, 79, 83, 87 with the support legs of the interior disks 30, 34, 36,44. The walls 40, 41, 42 of interior disks 30, 34, 36, 44 form thegrooved slots for holding solid precursors. Exterior disks 62, 78, 82,86 comprise walls 68, 69, 70 for holding solid precursors. Duringassembly, the solid precursors are loaded into the annular slots 47, 48,49 of interior disks 30, 34, 36, 44 and annular slots 64, 65, 66 ofexterior disks 62, 78, 82, 86.

While FIG. 3 discloses one embodiment of a sublimator capable ofdelivering the vapor of any solid Ti-containing film forming compositionto the reactor, one of ordinary skill in the art will recognize thatother sublimator designs may also be suitable, without departing fromthe teachings herein. Finally, one of ordinary skill in the art willrecognize that the disclosed Ti-containing film forming composition 11may be delivered to semiconductor processing tools using other deliverydevices, such as the ampoules disclosed in WO 2006/059187 to Jurcik etal., without departing from the teachings herein.

The reaction chamber may be any enclosure or chamber of a device inwhich deposition methods take place, such as, without limitation, aparallel-plate type reactor, a cold-wall type reactor, a hot-wall typereactor, a single-wafer reactor, a multi-wafer reactor, or other suchtypes of deposition systems. All of these exemplary reaction chambersare capable of serving as an ALD reaction chamber. The reaction chambermay be maintained at a pressure ranging from about 0.5 mTorr to about 20Torr, preferably between about 0.1 Torr and about 5 Torr. In addition,the temperature within the reaction chamber may range from about 50° C.to about 600° C. One of ordinary skill in the art will recognize thatthe optimal deposition temperature range for each Ti halide-containingprecursors may be determined experimentally to achieve the desiredresult.

The reactor contains one or more substrates onto which the thin filmswill be deposited. A substrate is generally defined as the material onwhich a process is conducted. The substrates may be any suitablesubstrate used in semiconductor, photovoltaic, flat panel, or LCD-TFTdevice manufacturing. Examples of suitable substrates include wafers,such as silicon, SiGe, silica, glass, or Ge. Plastic substrates, such aspoly(3,4-ethylenedioxythiophene)poly (styrenesulfonte) [PEDOT:PSS], mayalso be used. The substrate may also have one or more layers ofdiffering materials already deposited upon it from a previousmanufacturing step. For example, the wafers may include silicon layers(crystalline, amorphous, porous, etc.), silicon oxide layers, siliconnitride layers, silicon oxy nitride layers, carbon doped silicon oxide(SiCOH) layers, or combinations thereof. Additionally, the wafers mayinclude copper, cobalt, ruthenium, tungsten and/or other metal layers(e.g. platinum, palladium, nickel, ruthenium, or gold). The wafers mayinclude barrier layers or electrodes, such as tantalum, tantalumnitride, etc. Plastic layers, such aspoly(3,4-ethylenedioxythiophene)poly (styrenesulfonate) [PEDOT:PSS] mayalso be used. The layers may be planar or patterned. The substrate maybe an organic patterned photoresist film. The substrate may includelayers of oxides which are used as dielectric materials in MIM, DRAM, orFeRam technologies (for example, ZrO₂ based materials, HfO₂ basedmaterials, TiO₂ based materials, rare earth oxide based materials,ternary oxide based materials, etc.) or from nitride-based films (forexample, TaN, TiN, NbN) that are used as electrodes. The disclosedprocesses may deposit the Ti-containing layer directly on the wafer ordirectly on one or more than one (when patterned layers form thesubstrate) of the layers on top of the wafer. Furthermore, one ofordinary skill in the art will recognize that the terms “film” or“layer” used herein refer to a thickness of some material laid on orspread over a surface and that the surface may be a trench or a line.Throughout the specification and claims, the wafer and any associatedlayers thereon are referred to as substrates. The actual substrateutilized may also depend upon the specific precursor embodimentutilized. In many instances though, the preferred substrate utilizedwill be those that suffer damage from the presence of chlorine in TiCl₄,such as titanium oxide, tungsten metal, or GeSbTe layers.

The disclosed processes may selectively deposit the Ti-containing film,particularly when the Ti-containing film forming composition is exposedto a substrate made of multiple different materials. For example,blocking agents such as self assembling monolayers (SAM) may prevent theadsorption of the Ti halide-containing precursor on a portion of thesubstrate. The SAMs prevent growth of the Ti-containing film on specificareas, or types, of substrate. Alternatively or in addition, a freeinhibitor may be added during the deposition process to preventadsorption of the Ti halide-containing precursor on a portion of thesubstrate. In some cases, the adduct liberated from the Ti-containingfilm forming composition may deposit on certain surfaces and inhibitgrowth of the Ti-containing film on such surfaces. For instance,S-containing adducts may bind to copper and prevent growth of theTi-containing film on copper. In other cases, TiX₄ may etch certainmetallic surfaces, such as Al. As a result, the Ti-containing film maynot grow on these surfaces. A selective deposition process may alsoresult from any combination of these physical phenomena. As a result,one of ordinary skill in the art will recognize that specificTi-containing film forming compositions will have different reactivateswith different substrates.

The temperature and the pressure within the reactor are held atconditions suitable for vapor depositions. In other words, afterintroduction of the vaporized composition into the chamber, conditionswithin the chamber are such that at least part of the vaporized Tihalide-containing precursor is deposited onto the substrate to form aTi-containing film. For instance, the pressure in the reactor may beheld between about 1 Pa and about 10⁵ Pa, more preferably between about25 Pa and about 10³ Pa, as required per the deposition parameters.Likewise, the temperature in the reactor may be held between about 100°C. and about 500° C., preferably between about 200° C. and about 450° C.One of ordinary skill in the art will recognize that “at least part ofthe vaporized Ti halide-containing precursor is deposited” means thatsome or all of the precursor reacts with or adheres to the substrate.

The temperature of the reactor may be controlled by either controllingthe temperature of the substrate holder or controlling the temperatureof the reactor wall. Devices used to heat the substrate are known in theart. The reactor wall may be heated to a sufficient temperature toobtain the desired film at a sufficient growth rate and with desiredphysical state and composition. A non-limiting exemplary temperaturerange to which the reactor wall may be heated includes fromapproximately 100° C. to approximately 500° C. When a plasma depositionprocess is utilized, the deposition temperature may range fromapproximately 50° C. to approximately 400° C. Alternatively, when athermal process is performed, the deposition temperature may range fromapproximately 200° C. to approximately 450° C.

In addition to the disclosed Ti-containing film forming composition, areactant may also be introduced into the reactor. The reactant may be anoxygen-containing gas such as one of O₂, O₃, H₂O, H₂O₂, NO, N₂O, NO₂, analcohol (such as ethanol or methanol), a diol (such as ethylene glycolor hydrated hexafluoroacetone), oxygen containing radicals such as O⁻ orOH⁻, NO, NO₂, carboxylic acids, formic acid, acetic acid, propionicacid, and mixtures thereof. Preferably, the oxidizing gas is selectedfrom the group consisting of O₂, O₃, H₂O, H₂O₂, oxygen containingradicals thereof such as O⁻ or OH⁻, and mixtures thereof.

Alternatively, the reactant may be H₂, NH₃, hydrazines (such as N₂H₄,MeHNNH₂, Me₂NNH₂, MeHNNHMe, phenyl hydrazine), organic amines (such asNMeH₂, NEtH₂, NMe₂H, NEt₂H, NMe₃, NEt₃, (SiMe₃)₂NH, cyclic amines likepyrrolidine or pyrimidine), nitriles (such as acetonitrile), diamines(such as ethylene diamine, dimethylethylene diamine, tetramethylethylenediamine), aminoalcohols (such as ethanolamine [HO—CH₂—CH₂—NH₂], bisethanolamine [HN(C₂H₅OH)₂] or tris ethanolamine[N(C₂H₅OH)₃]),pyrazoline, pyridine, radicals thereof, or mixtures thereof. Preferablythe reactant is H₂, NH₃, radicals thereof, or mixtures thereof.

In another alternative, the reactant may be N(SiH₃)₃;N(SiH_(x)R_(3-x))₃, with each x independently 1-3 and each Rindependently alkyl or NR′₂, with each R′ independently H or C1-C4 alkyl(such as (H₃Si)₂N(SiH₂NEt₂), (H₃Si)₂N(SiH₂NiPr₂), or (H₃Si)₂N(SiH₂iPr));R₃Si—NH—SiR₃, with each R independently H, Cl, Br, I, or a C1-C4 alkylgroup (such as H₃Si—NH—SiH₃, H₂ISi—NH—SiH₃,or Me₃Si—NH—SiMe₃);hydridosilanes (such as SiH₄, Si₂He, Si₃H, Si₄H₁₀, Si₅H₁₀, Si₅H₁₂);chlorosilanes and chloropolysilanes (such as SiHCl₃, SiH₂Cl₂, SiH₃Cl,Si₂Cl₆, Si₂HCl₆, Si₃Cl₈); bromosilanes and bromopolysilanes (such asSiHBr₃, SiH₂Br₂, SiH₃Br, Si₂Br₆, Si₂HBr₅, Si₃Br₈); iodosilanes andiodopolysilanes (such as SiHI₃, SiH₂I₂, SiH₃I, Si₂I₆, Si₂HI₅, Si₃I₈);alkylsilanes (such as Me₂SiH₂, Et₂SiH₂, MeSiH₃, EtSiH₃); andaminosilanes (such as tris(dimethylamino)silane,bis(diethylamino)silane, di-isopropylaminosilane and other mono, bis ortris aminosilanes); radicals thereof; or mixtures thereof. Preferably,the reactant is (SiH₃)₃N or an aminosilane, such asbis(diethylamino)silane.

The reactant may be treated by a plasma, in order to decompose thereactant into its radical form. N₂ may also be utilized as a reducinggas when treated with plasma. For instance, the plasma may be generatedwith a power ranging from about 50 W to about 2500 W, preferably fromabout 100 W to about 400 W. The plasma may be generated or presentwithin the reactor itself. Alternatively, the plasma may generally be ata location removed from the reactor, for instance, in a remotely locatedplasma system. One of skill in the art will recognize methods andapparatus suitable for such plasma treatment.

For example, the reactant may be introduced into a direct plasmareactor, which generates plasma in the reaction chamber, to produce theplasma-treated reactant in the reaction chamber. Exemplary direct plasmareactors include the Titan™ PECVD System produced by Trion Technologies.The reactant may be introduced and held in the reaction chamber prior toplasma processing. Alternatively, the plasma processing may occursimultaneously with the introduction of the reactant. In-situ plasma istypically a 13.56 MHz RF inductively coupled plasma that is generatedbetween the showerhead and the substrate holder. The substrate or theshowerhead may be the powered electrode depending on whether positiveion impact occurs. Typical applied powers in in-situ plasma generatorsare from approximately 30 W to approximately 1000 W. Preferably, powersfrom approximately 30 W to approximately 600 W are used in the disclosedmethods. More preferably, the powers range from approximately 100 W toapproximately 500 W. The disassociation of the reactant using in-situplasma is typically less than achieved using a remote plasma source forthe same power input and is therefore not as efficient in reactantdisassociation as a remote plasma system, which may be beneficial forthe deposition of Ti-containing films on substrates easily damaged byplasma.

Alternatively, the plasma-treated reactant may be produced outside ofthe reaction chamber. The MKS Instruments' ASTRONi® reactive gasgenerator may be used to treat the reactant prior to passage into thereaction chamber. Operated at 2.45 GHz, 7 kW plasma power, and apressure ranging from approximately 0.5 Torr to approximately 10 Torr,the reactant O₂ may be decomposed into two O radicals. Preferably, theremote plasma may be generated with a power ranging from about 1 kW toabout 10 kW, more preferably from about 2.5 kW to about 7.5 kW.

The vapor deposition conditions within the chamber allow the disclosedTi-containing film forming composition and the reactant to react andform a Ti-containing film on the substrate. In some embodiments,Applicants believe that plasma-treating the reactant may provide thereactant with the energy needed to react with the disclosed composition.

Depending on what type of film is desired to be deposited, an additionalprecursor compound may be introduced into the reactor. The precursor maybe used to provide additional elements to the Ti-containing film. Theadditional elements may include lanthanides (e.g., Ytterbium, Erbium,Dysprosium, Gadolinium, Praseodymium, Cerium, Lanthanum, Yttrium),germanium, silicon, aluminum, boron, phosphorous, hafnium, zirconium, aGroup 3 element (i.e., Sc, Y, La, or Ac), or a Group 5 element (i.e., V,Nb, or Ta), or mixtures of these. When an additional precursor compoundis utilized, the resultant film deposited on the substrate contains Tiin combination with at least one additional element.

When the resulting film contains Al, suitable reactants includetrialkylaluminum (e.g., AlMe₃, AlEt₃, etc.), dialkylaluminum halide(e.g., AlMe₂Br, AlEt₂Br, etc.), alkylaluminum dihalide (e.g., AlMeBr₂,AlEtBr₂, etc.), alkylamino or alkoxy derivatives of aluminum (e.g.,Al(NEt₂)₃, Al(OtBu)₃, etc.), alanes, amine-adducted alanes (e.g.,Al:NEt₃), and mixtures thereof. The resulting amorphous TiAl film may beused for micromirror arrays in complementary metal oxide semiconductors(CMOS). Schmidt et al., J. of Micro/Nanolithography, MEMS, and MOEMS,7(2) 2008. Vapor deposition of the amorphous TiAl film provides betterconformality, surface smoothness, compositional uniformity, and ingeneral fewer defects than those produced by sputtering.

The Ti-containing film forming compositions and reactants may beintroduced into the reactor either simultaneously (chemical vapordeposition), sequentially (atomic layer deposition) or differentcombinations thereof. The reactor may be purged with an inert gasbetween the introduction of the composition and the introduction of thereactant. Alternatively, the reactant and the composition may be mixedtogether to form a reactant/compound mixture, and then introduced to thereactor in mixture form. Another example is to introduce the reactantcontinuously and to introduce the Ti-containing film forming compositionby pulse (pulsed chemical vapor deposition).

The vaporized composition and the reactant may be pulsed sequentially orsimultaneously (e.g. pulsed CVD) into the reactor. Each pulse ofcomposition may last for a time period ranging from about 0.01 secondsto about 100 seconds, alternatively from about 0.3 seconds to about 30seconds, alternatively from about 0.5 seconds to about 10 seconds. Thereactant may also be pulsed into the reactor. In such embodiments, thepulse of each gas may last from about 0.01 seconds to about 100 seconds,alternatively from about 0.3 seconds to about 30 seconds, alternativelyfrom about 0.5 seconds to about 10 seconds. In another alternative, thevaporized composition and one or more reactants may be simultaneouslysprayed from a shower head under which a susceptor holding severalwafers is spun (spatial ALD).

Depending on the particular process parameters, deposition may takeplace for a varying length of time. Generally, deposition may be allowedto continue as long as desired or necessary to produce a film with thenecessary properties. Typical film thicknesses may vary from severalangstroms to several hundreds of microns, depending on the specificdeposition process. The deposition process may also be performed as manytimes as necessary to obtain the desired film.

In one non-limiting exemplary CVD type process, the vapor phase of thedisclosed Ti-containing film forming composition and a reactant aresimultaneously introduced into the reactor. The two react to form theresulting Ti-containing thin film. When the reactant in this exemplaryCVD process is treated with a plasma, the exemplary CVD process becomesan exemplary PECVD process. The reactant may be treated with plasmaprior or subsequent to introduction into the chamber.

In one non-limiting exemplary ALD type process, the vapor phase of thedisclosed Ti-containing film forming composition is introduced into thereactor, where the Ti halide-containing precursor physi- or chemisorbson the substrate. Excess composition may then be removed from thereactor by purging and/or evacuating the reactor. A desired gas (forexample, O₃) is introduced into the reactor where it reacts with thephysi- or chemisorped precursor in a self-limiting manner. Any excessreducing gas is removed from the reactor by purging and/or evacuatingthe reactor. If the desired film is a Ti metal film, this two-stepprocess may provide the desired film thickness or may be repeated untila film having the necessary thickness has been obtained.

Alternatively, if the desired film contains the Ti metal and a secondelement, the two-step process above may be followed by introduction ofthe vapor of an additional precursor compound into the reactor. Theadditional precursor compound will be selected based on the nature ofthe Ti metal film being deposited. After introduction into the reactor,the additional precursor compound is contacted with the substrate. Anyexcess precursor compound is removed from the reactor by purging and/orevacuating the reactor. Once again, a desired gas may be introduced intothe reactor to react with the precursor compound. Excess gas is removedfrom the reactor by purging and/or evacuating the reactor. If a desiredfilm thickness has been achieved, the process may be terminated.However, if a thicker film is desired, the entire four-step process maybe repeated. By alternating the provision of the Ti-containing compound,additional precursor compound, and reactant, a film of desiredcomposition and thickness can be deposited.

When the reactant in this exemplary ALD process is treated with aplasma, the exemplary ALD process becomes an exemplary PEALD process.The reactant may be treated with plasma prior or subsequent tointroduction into the chamber.

In a second non-limiting exemplary ALD type process, the vapor phase ofone of the disclosed Ti halide-containing precursors, for exampleTiBr₄:S(nPr)₂, is introduced into the reactor, where it is contactedwith a TiO substrate. Excess Ti halide-containing precursor may then beremoved from the reactor by purging and/or evacuating the reactor. Adesired gas (for example, NH₃) is introduced into the reactor where itreacts with the absorbed Ti halide-containing precursor in aself-limiting manner to form a TiN film. Any excess N-containing gas isremoved from the reactor by purging and/or evacuating the reactor. Thesetwo steps may be repeated until the TiN film obtains a desiredthickness.

The Ti-containing films resulting from the processes discussed above mayinclude a titanium oxide (Ti_(n)O_(m), wherein each n and m is aninteger which inclusively ranges from 1 to 6), such as TiO₂; a titaniumnitride, such as TiN or TiSiN; a titanium oxide containing anotherelement M (TiM_(i)O_(x), wherein i ranges from 0.1 to 1; x ranges from 1to 6; and M is selected from zirconium, hafnium, a Group 3 element, aGroup 5 element, a lanthanide, Si, Al, B, P or Ge); or a titaniumoxynitride (TiM′_(i)N_(y)O_(x), wherein i ranges from 0 to 1; x and yrange from 1 to 6; and M′ is selected from hafnium, zirconium, a Group 3element, a Group 5 element, a lanthanide, Si, Al, B, P or Ge). One ofordinary skill in the art will recognize that by judicial selection ofthe appropriate disclosed compound, optional precursor compounds, andreactant species, the desired film composition may be obtained.

The Ti-containing film forming composition may be used to deposit Ti ona silicon layer and annealed to form a TiSi₂ layer. Alternatively, theTi-containing film forming composition and a Si-containing reactant,such as TSA, may be used to form a TiSi₂ layer. In either alternative,the TiSi₂ layer formed preferably exhibits C54 polymorphism and aresistivity between approximately 10 _(u)Ωcm and approximately 20_(u)Ωcm, preferably between approximately 13 _(u)Ωcm and approximately16 _(u)Ωcm. Alternatively, if a higher resistivity is desired, a C49polymorphic TiSi₂ layer may be formed. The C49 polymorphic TiSi₂ layerhas a resistivity between approximately 60 _(u)Ωcm and approximately 70_(u)Ωcm. The polymorphic phase may be determined using XRD.

The Ti-containing films resulting from the processes discussed abovecontain between approximately 0 atomic % to approximately 5 atomic % ofC; between approximately 0 atomic % to approximately 40 atomic % of O;between approximately 0 atomic % to approximately 2 atomic % of S;between approximately 0 atomic % to approximately 2 atomic % of Se;between approximately 0 atomic % to approximately 2 atomic % of Te; orbetween approximately 0 atomic % to approximately 2 atomic % of Pimpurities (depending on the adduct composition).

Upon obtaining a desired film thickness, the film may be subject tofurther processing, such as thermal annealing, furnace-annealing, rapidthermal annealing, UV or e-beam curing, and/or plasma gas exposure.Those skilled in the art recognize the systems and methods utilized toperform these additional processing steps. For example, theTi-containing film may be exposed to a temperature ranging fromapproximately 200° C. and approximately 1000° C. for a time ranging fromapproximately 0.1 second to approximately 7200 seconds under an inertatmosphere, a H-containing atmosphere, a N-containing atmosphere, anO-containing atmosphere, or combinations thereof. Most preferably, thetemperature is 400° C. for 3600 seconds under a H-containing atmosphereor an O-containing atmosphere. The resulting film may contain fewerimpurities and therefore may have an improved density resulting inimproved leakage current. The annealing step may be performed in thesame reaction chamber in which the deposition process is performed.Alternatively, the substrate may be removed from the reaction chamber,with the annealing/flash annealing process being performed in a separateapparatus. Any of the above post-treatment methods, but especiallythermal annealing, has been found effective to reduce carbon andnitrogen contamination of the Ti-containing film. This in turn tends toimprove the resistivity of the film.

EXAMPLES

The following examples illustrate experiments performed in conjunctionwith the disclosure herein. The examples are not intended to be allinclusive and are not intended to limit the scope of disclosuredescribed herein.

Due to its hygroscopic nature, the TiX₄ reactants and TiX_(n):L_(y)adducts were all handled in a glove box under dried inert atmosphere.The various Lewis base ligands were dried and stored under argon usingstandard drying techniques, such as molecular sieves or other desiccanttreatment.

Example 1: Synthesis of TiBr₄:S(nPr)₂

0.5 g of solid TiBr₄ was reacted with 1 molar equivalent of S(nPr)₂ in aglove box. An exotherm and immediate color change to dark red wasobserved. Almost no solid particles remained. After 15 minutes, themixture was filtered using a syringe plug filter to produce a clear darkred liquid. According to Baker et al., the resulting product ismonosubstituted and adopts a penta-coordinated trigonal bipyramidalgeometry:

FIG. 4 is a ¹H-NMR spectrum of the resulting product in C₆D₆. The cleanspectrum shows no impurities. The α-Ti ¹H splitting suggests magneticinequivalence of the two propyl groups, which may be due to therestricted conformation of the ligand.

FIG. 5 is a ThermoGravimetric Analysis/Differential Thermal Analysis(TGA/DTA) graph illustrating the percentage of weight loss (TGA) or thedifferential temperature (DTA) of TiBr₄:S(nPr)₂ in an Al₂O₃ pan upontemperature increase at 1 atmosphere. The TGA results demonstrate cleanevaporation (<0.5% residue). No residue was obtained when the TGAanalysis was performed at reduced pressure (˜12 Torr).

Example 2: Synthesis of TiBr₄:SEtPr

0.5 g of solid TiBr₄ were reacted with 1 molar equivalent of SEtPr in aglove box. An exothermic reaction and immediate color change from orangeto dark red was observed. Almost no solid particles remained. Afterstirring for 15 minutes, the mixture was filtered using a syringe plugfilter to produce a clear dark red liquid.

FIG. 6 is a ¹H-NMR spectrum of the resulting product in CeDe. The cleanspectrum shows no impurities.

FIG. 7 is a TGA/DTA graph illustrating the percentage of weight loss(TGA) or the differential temperature (DTA) of TiBr₄:S(nPr)₂ in an Al₂O₃pan upon temperature increase at 1 atmosphere. The TGA resultsdemonstrate clean evaporation (<0.5% residue). No residue was obtainedwhen the TGA analysis was performed at reduced pressure (˜12 Torr).

Example 3: Atomic Layer Deposition (ALD) of TiBr₄:S(nPr)₂

ALD of TiN was performed using the liquid TiBr₄:S(nPr)₂ prepared inExample 1. FIG. 8 is a flow chart showing the ALD process. In Step 1, a3 second pulse of NH₃ is introduced into a reaction chamber (not shown)containing a SiO₂ substrate and reacts with the substrate to produce theNH₂-terminated substrate of FIG. 9. The reactor was maintained at 200°C., 300° C., and 400° C. at 1 Torr. The 3 second NH₃ pulse is followedby a 10 second Ar purge pulse to remove any excess NH₃ or reactionby-products.

In Step 2 of FIG. 8, a 6 second pulse of the vapor form of theTiBr₄:S(nPr)₂ precursor is introduced into a reaction chamber. Theliquid TiBr₄:S(nPr)₂ precursor of Example 1 was placed in a vesselheated and maintained at 72° C. to produce the vapor form. The vesselutilized a cross flow configuration, in which the ends of the inletconduit and outlet conduit were both located above the surface of theTi-containing film forming composition. FIG. 10 is a schematic side viewof the substrate at the start of Step 2. FIG. 11 is a schematic sideview of the reaction between the TiBr₄:S(nPr)₂ precursor with thesubstrate as well as the reaction by-products, such as HBr and S(nPr)₂.The S(nPr)₂ reaction by-product is produced by cleavage of the S(nPr)₂adduct from the TiBr₄:S(nPr)₂ precursor. The HBr reaction by-product isproduced by the reaction between the —NH₂ substrate surface and one Brof the TiBr₄:S(nPr)₂ precursor.

In Step 3 of FIG. 8, a ten second argon pulse purges any excessTiBr₄:S(nPr)₂ precursor and reaction by-products from the reactionchamber to produce the substrate of FIG. 12.

In Step 4 of FIG. 8, the process may be repeated if the desired filmthickness has not been obtained by introducing the 3 second NH₃ pulse ofStep 1. FIG. 13 is a schematic side view of the reaction between thesubstrate of FIG. 12 with the NH₃ reactant of Step 1 of FIG. 8, as wellas the reaction by-products, such as HBr. The HBr reaction by-product isproduced by reaction of one Br of the TiBr₃ substrate with one H of theNH₃ reactant. The 3 second NH₃ pulse is followed by a 10 second Ar purgepulse to remove any excess NH₃ or reaction by-products.

ALD saturation behavior was observed at 400° C. with a growth rate of0.57 Å/cycle on silicon dioxide substrate (SiO₂). 74% step coverage wasobtained after 300 cycles on a feature having a 1:20 aspect ratio.

FIG. 14 is a graph demonstrating (a) the growth rate and (b) filmthickness of TiN thin films using TiBr₄:S(nPr)₂/NH₃ as a function of thesubstrate temperature between 200 and 400° C. Linear growth wasobserved.

The stoichiometry of some TiN films was analysed by XPS (X rayPhotoelectron Spectroscopy). However, the films contained a large amountof oxygen. The oxygen may have been the result of handling the filmsunder atmosphere after completion of the deposition process.Nonetheless, the Ti:N ratio of the films was approximately 1:1.

COMPARATIVE EXAMPLE

Comparative ALD of TiN was performed using solid TiBr₄. TiBr₄ was placedin a vessel heated and maintained at 55° C. The reactor was maintainedat 200° C., 300° C., and 500° C. at 0.5 Torr. Length of TiBr₄introduction, argon purge, NH₃ introduction, and argon purge was 3seconds, 10 seconds, 2 seconds, and 10 seconds, respectively. ALDsaturation behavior was observed at 300° C. and 500° C. with a growthrate of 0.57 and 056 Å/cycle, respectively, on silicon wafer (Si). 74.5%step coverage was obtained after 200 cycles on a feature having a 1:20aspect ratio.

As can be seen, the ALD results using the liquid TiBr₄:S(nPr)₂ precursorwere similar to those obtained using the solid TiBr₄ precursor. However,the liquid TiBr₄:S(nPr)₂ precursor is much easier to handle than thesolid TiBr₄ precursor.

It will be understood that many additional changes in the details,materials, steps, and arrangement of parts, which have been hereindescribed and illustrated in order to explain the nature of theinvention, may be made by those skilled in the art within the principleand scope of the invention as expressed in the appended claims. Thus,the present invention is not intended to be limited to the specificembodiments in the examples given above and/or the attached drawings.

We claim:
 1. A method of depositing a Ti-containing film on a substrate,the method comprising introducing, into a reactor containing thesubstrate, a Ti-containing film forming composition comprising atitanium halide-containing precursor having the following formula:TiX_(b):A_(c) with b=3 or 4; c=1-3; X=Br or I; A=SRR′, SeRR′, or TeRR′,and R and R′ are independently H or a C1-C5 hydrocarbon, wherein the Tihalide-containing precursor is a liquid at standard temperature andpressure, and depositing at least part of the Ti halide-containingprecursor onto the substrate to form the Ti-containing film.
 2. Themethod of claim 1, further comprising introducing a reactant into thereactor.
 3. The method of claim 1, wherein the Ti-containing film isselectively deposited onto the substrate.
 4. The method of claim 1,wherein the Ti-containing film forming composition comprises a titaniumhalide-containing precursor having the formula TiBr₄:(SRR′)₂.
 5. Themethod of claim 4, wherein the Ti-containing film forming compositioncomprises a titanium halide-containing precursor having the formulaTiBr₄:S(nPr)₂.
 6. The method of claim 1, wherein the Ti-containing filmforming composition comprises a titanium halide-containing precursorhaving the formula TiBr₄:SEt(nPr).
 7. The method of claim 1, wherein thetitanium-containing film forming composition further comprises greaterthan 0% w/w and no more than 0.2% w/w of a mixture of oxyhalide(TiX₂(═O)), hydroxyhalide (TiX₃(OH)), and oxides (TiO₂).
 8. The methodof claim 1, wherein the titanium-containing film forming compositionfurther comprises between greater than 0% w/w and 0.1% w/w of hydrogenhalide (HX).
 9. The method of claim 1, wherein the titanium-containingfilm forming composition further comprises between greater than 0% w/wand 5% w/w of a hydrocarbon solvent or of free adduct.
 10. The method ofclaim 1, wherein the titanium-containing film forming compositionfurther comprises between greater than 0% w/w and 5 ppmw of H₂O.
 11. Themethod of claim 1, wherein X is Br.
 12. The method of claim 1, wherein Xis I.
 13. The method of claim 1, wherein A is SRR′.
 14. The method ofclaim 1, wherein A is SeRR′.
 15. The method of claim 1, wherein A isTeRR′.